Biological treatment is possible by harnessing plants and microbes’ natural ability to absorb phosphorus, nitrogen, and other nutrients to break down contaminants through a biological process known as bioremediation. Bioremediation is used to capture and remove contaminants using wetlands and is practiced worldwide.
Biofiltration for Wastewater Treatment
Biofiltration was introduced in 1893 in England as a filter for wastewater treatment. Since then, it has been successfully used to treat different types of water. Biological treatment has been used in Europe since the early 1900s to filter surface water for drinking purposes and is receiving more worldwide interest. Biofiltration is common in wastewater treatment, greywater recycling, and aquaculture to increase water quality while minimizing water replacement.
A bed of media, a biofilter, is the material in which plants grow to form a biofilm layer. Biofiltration is commonly called a fixed-film process. The biofilm is formed by different microorganisms, such as yeast, bacteria, or fungi, macro-organisms such as insects’ larvae, protozoa, worms, and extracellular polymeric substances. The biofilm is slimy and muddy.
The water that is to be treated can be intermittently applied or continuously applied over the media, using upflow or downflow. Usually, a biofilter has two or three phases depending on the feeding strategy.
A solid-phase — media
A liquid phase — water
A gas-phase — air
Organic matter plus other water components are distributed into the biofilm as the treatment happens. Biofiltration processes are aerobic, which means that microorganisms require oxygen for metabolism. Oxygen is supplied to the biofilm with water flow. Aeration passively occurs by the natural flow of air or by forced air provided by blowers.
The activity of the microorganisms is a vital part of the performance process. The influencing factors are water composition, type of media, feeding strategy, biofilter hydraulic loading, age of the biofilm, temperature, aeration, etc.
Biofilters
Most biofilters use media such as river gravel, sand, crushed rock, or some form of plastic or ceramic material resembling small rings and beads.
Although biological filters have simple superficial structures, their internal workings, biology, and ecology are complex and variable. The process can maintain its performance or return to initial levels following a period of no flow, intense use, media backwash, toxic shocks, etc.
The biofilm protects microorganisms from demanding environmental conditions and retains the biomass even when conditions are not optimal for its growth. The advantages of the biofiltration process are:
Biofiltration allows the development of microorganisms with low growth rates because they are retained within the biofilm.
Biofilters are less subject to intermittent or variable loading or hydraulic shock.
Operational costs are usually lower.
The final treatment result is less influenced by biomass separation.
The attached biomass becomes more specialized at a given point because there is no biomass return.
Because filtration and biomass growth leads to an accumulation of matter in the filtering media, this process is subject to flow channeling and bio-clogging. Bio-clogging can be controlled depending on the type of application and the media used for microbial growth with chemical or physical methods.
Drinking Water
For drinking water, biological water treatment involves using naturally occurring microorganisms in the surface water, improving the water quality. Under optimum conditions, such as high oxygen content, the organisms break down the material in the water, improving its quality. Sand filters or carbon filters can be used to provide support for the microorganisms to grow. These systems effectively reduce diseases that are water-borne, improving water quality.
Bioremediation is Important
Clearly, bioremediation is very important for treating water. Any time we can find natural ways to clean our earth’s water, we must use them. Creating wetland filters, filter beds, filter swales, rain gardens, and floating plant islands are all ways that we as homeowners can use biological means to help clean the water on our properties. While these homeowner solutions aren’t as complex or detailed as wastewater biofiltration systems, they use many of the same principles.
Pond water ecology is the circle of life within your pond. Natural pond balance works, but most people do not have the patience to wait for nature to take its course. Many companies promote needless monthly chemical applications to maintain ponds. This chemical burden is entirely unnecessary and detrimental to your pond and the environment as a whole. Their job is to sell you products, pure and simple. They are not concerned for the health of your pond.
It’s About Balance not Chemicals
When naturally balanced, the pond will eventually do very well on its own without help from us or chemicals.
With chemical use, it is a vicious cycle of killing algae with chemicals. The dead algae go to the bottom and create more nutrients for the next algae bloom as the chemicals wear off. Therefore, most natural bottomed retention ponds are a nightmare for their owners, as chemical treatments result in thick muck at the bottom and recurring algae blooms.
Pond ecology is the interaction of the life in the pond with the existing environment. A shallow pond that is nutrient-rich will be filled with algae and aquatic plants if exposed to the sun with little water flow through it. It has little animal life because of the low oxygen levels.
In contrast, a newly created spring-fed pond may have little life of any kind due to low temperatures and lack of food supply.
A healthy freshwater pond has the following layers:
Bottom: There is very little sunlight or oxygen at the pond’s bottom. Decomposition occurs, and scavengers live here to feed on dead materials, such as water worms and grubs.
Midwater: Fish are the main predators. Food is found on the surface of the pond or the pond bottom. Animals found here breathe through their gills or skin, for example, dragonflies, water fleas, or stickleback fish.
Pond surface: Animals found here breathe through their lungs, gills, or skin. There is enough light and oxygen here. Animals found here include tadpoles, ducks, or midge larvae.
Pond margin: Plants provide a sheltered habitat for insects or small animals, such as frogs. Oxygen and light are abundant, so plants such as marsh marigolds and other marginal aquatics can thrive.
Above the pond’s surface: Insects such as dragonflies and birds such as kingfishers are prevalent here.
A Pond’s Life
A pond begins with mostly water, a few nutrients, and limited aquatic life. As the pond ages, the pond gathers nutrients. This process of enrichment is eutrophication. The addition of nutrients stimulates the growth of aquatic life. The organisms live, grow, then die.
Their remains and whatever else falls into the pond like leaves and debris decay in the pond. The nutrients in the plant debris are released back into the pond to keep the cycle going. With time, there will be an accumulation of material that resists decay. The pond will fill up, become a bog, and someday resemble dry land. This process of returning to dry land can occur in a decade or take centuries. It is the pond owners’ job to slow down this process as much as possible.
How to Slow Down the Process
Exclude the Basic Elements Needed to Make Aquatic Organisms
There are four essential elements needed to make aquatic organisms – carbon, nitrogen, oxygen, and phosphorous. These materials are required in abundance, along with other factors. To prevent the rapid aging of a pond (eutrophication), exclude the introduction of phosphorus and nitrogen. There are three methods helpful in slowing the aging process.
Buffers
We need to limit the nutrients coming into our pond, so animal access to streams or ponds should be restricted, and runoff controlled to limit phosphorus and nitrogen inputs from the waste.
Maintaining vegetation buffers in the areas where water must flow through to reach the pond is beneficial. Buffers slow down the water and filter it. Slow-moving water permits sediment to drop out of the water. Phosphorus attaches to soil particles, so sedimentation helps keep phosphorus out of the pond. Keeping sediment out of the pond prevents it from becoming shallow.
This directly contributes to the primary goal of keeping the pond from returning to dry land. A deeper pond will also be cooler. One of the general principles of biology is lower temperatures slow the growth of organisms, so the buffer area contributes to conditions that help slow the pond’s aging process.
Sedimentation
Providing a shallow pool at the pond’s inlet is another method of keeping sediment out of ponds. Water that passes through the pool will drop sediment into the pool on its way to the pond. The pool should be of a dimension enabling it to be easily cleaned with a backhoe from the shore. A sedimentation pool will help the pond in a similar way to buffer strips, but sediment ponds work well if the water’s inflow is too much and too concentrated for buffers.
Limit the Use of Fertilization
flamingos in a pond
If it is possible to decrease fertilizer use on crops or turf grown in the pond’s watershed area, it will benefit. We can assume that anything applied to the ground anywhere within the watershed will eventually make its way to the pond.
Plants are never 100% efficient in their use of fertilizer elements. So, even at appropriate rates, applying fertilizers results in excess nitrogen getting into your pond. Also, any animals that use the watershed will leave waste, increasing nutrients in the pond.
Maintaining Ecological Balance
koi in a pond
Ponds are most effective when there is a balanced and complete food web in place. This means that planktonic algae are present in sufficient quantity to feed zooplankton. The zooplankton then becomes food for aquatic insects and the smallest fish. These will then become prey for larger fish, finally to be food for heron, mink, raccoons, bears, or fishers.
Another part of maintaining ecological balance involves the higher plant community. Some pond owners are discouraged by too many plants in their pond. While a pond full of vegetation is not recommended, a nice balance of pond plants is required to maintain balance. From some pond owner’s viewpoint, a pond with vegetation along the shore is unsightly, so they often eliminate all pond plants and buffer plants and mow lawn right up to the shore.
The Clean Look?
Many like the “clean” look, so they kill plants with herbicide, fertilize their lawn right up to the waters’ edge, and then complain when their pond is overgrown with algae. This eventually leads them to dump chemicals in the pond to kill the algae and restore the “clean” look. Unfortunately, a pond like this is the opposite of clean. It is dead to most pond life and full of nutrients, just waiting for the chemicals to wear off to start another grand algae bloom.
Aquatic Plants
lilies on a pond
Aquatic plants can provide shade, places for small fish to hide, habitat for aquatic insects and animals, and food sources for some animals and fish. They are a vital part of the pond ecosystem, and they compete with the algae for nutrients, keeping it in check. It is about balance, not a clean look. A balanced pond is very clean and healthy.
There are certainly examples of too much vegetation in the pond. A pond completely covered with lotus or water lilies shade the pond so no other vegetation will grow under the water. There will not be enough light to grow planktonic algae, resulting in a pond that will be unproductive for anything besides lily growth.
Another example is the excessive growth of Watermeal or duckweed. When the entire pond surface is covered with these plants, the light is restricted, and the pond will contain little life beneath the surface. These plants virtually eliminate oxygenation of the water by maintaining the separation of the water surface from the atmosphere. As a result, the pond becomes deficient in oxygen to the extent that any fish present are killed.
You will notice that these are problems of extremes. Just like the extreme of too many plants results in negative consequences, so do too few plants.
Maintain Water Flow
A pond with continuous water flow will be more well-balanced than a pond with an intermittent flow. Water flow increases the water’s oxygenation and helps to reduce stratification. Also, new water entering the pond is important. While fresh water does indeed bring more nutrients, it also brings more oxygenation. A pond will lose significant water due to evaporation during the summer months. Ponds with sufficient inflow will stay full and refreshed, while the water levels of ponds without inflow will decline, resulting in lower oxygen levels in the water and less life.
Aeration
The pond’s overall health is dependent on oxygen in the pond water. Its value to the fish is obvious. Less obvious but essential is the pond’s ability to eliminate waste. The waste that happens in the pond includes waste from animal life such as geese and fish and the waste that falls into the pond like leaves, debris, and grass clippings. These waste materials can enter with stormwater runoff, wind, and along with animals and plants that die in the pond.
Bacteria and enzymes are needed to break down and consume all of this debris. Aerobic bacteria perform twenty times quicker than anaerobic bacteria to break down the waste. It can then be flushed out or is available to grow new life. The oxygenation of a pond is quite interesting. It occurs in two primary ways.
Photosynthesis
Algae and plants do photosynthesis during the day, with the wind adding oxygen at night. The oxygen that plants produce is released into the pond, helping maintain water oxygen levels. Conditions that prevent light and oxygen from entering the pond need to be monitored. A pond completely covered with watermeal can be in trouble in a hurry. All of the oxygen produced by the Watermeal is released into the atmosphere rather than into the pond.
Any part of the pond that is too dark for photosynthesis is likely oxygen-deficient unless the water column is circulated. Scientists use a Secchi disk to measure water transparency. The level at which they can no longer see the disk from the surface is the depth to which the pond will be oxygenated through photosynthesis. Anything below that level needs to be circulated to receive oxygen.
At the Surface of the Pond
the pond surface
Another method of getting oxygen into the pond water occurs by an oxygen exchange with the atmosphere at the pond’s surface. The rougher the surface is, the more rapid the exchange. Also, the more deficient the oxygen supply is in the water, the faster the exchange will occur.
This process is critical at night and essential for a pond with a heavy load of animals and plants. During the night, plants perform respiration rather than photosynthesis. The pond could be oxygen-deficient by morning if atmospheric aeration has been impeded by lack of wind or a covered surface.
We can significantly increase our ponds aeration by installing a bottom aeration system. Pumping air bubbles to the bottom of a pond will increase oxygen levels and circulate water, providing a better balance.
Pond Ecology in Winter
In the winter, as the water gets much colder, with ice covering the top of the pond for an extended period, the pond ecology changes.
Amphibians such as turtles, frogs, and fish have adaptive features that enable them to adjust to this less friendly environment. Their body temperature will drop with the water temperature, decreasing their energy requirements and respiration rate. Turtles and frogs burrow into the mud at the pond’s bottom and hibernate.
Ice prohibits oxygen entry into the pond through the surface; however, sunlight that gets through the ice will allow for some photosynthesis by the aquatic plants. An entirely snow-covered pond can quickly become depleted of oxygen, killing frogs, turtles, and fish.
A smaller, more shallow water body is more susceptible to this than a larger, deeper body of water simply due to the quantity of water. We can help this problem in our small ponds by providing bottom aeration, which will pump oxygen to the bottom of the pond all winter long to keep the water oxygenated. If we can’t aerate and if the ice is safe to walk on, we can clear lanes across the pond to remove some of the snow to let in the sunlight.
Changes to a Pond’s Ecosystem
Ecosystems are sensitive to change. Human or natural factors can alter the system’s living and non-living components.
Natural factors which cause adverse changes to the ecosystem can include:
Disease
Drought
Fire
Flood
Heat
Debris
Ice and Snow cover
Excessive plant growth (invasives)
Excessive animal use (geese, ducks, etc.)
Human factors which cause adverse changes to the ecosystem can include:
Altering the drainage of the land, which can influence the quantity of water
Altering the nutrient levels of the water with fertilizers, resulting in eutrophication.
Chemical pond additives destroying the aquatic balance
Mechanical sterilizers destroying the aquatic balance
Allowing heavy debris loads into the pond
Removing too many plants from a pond
Electric current entering the pond
Excessive livestock use of the pond
Pumping from a pond for irrigation
Summary
Long pond life is best achieved by maintaining a healthy ecosystem. Your pond’s ecosystem is all about balance. When any one of the above factors gets out of balance, there will be consequences. Humans are the biggest disruptors of pond balance. When we see a pond with excessive algae growth, we shouldn’t ask, “what’s wrong with the pond?” we should ask, “what have we done to the pond to push it out of balance?”
By limiting the input of nutrients into the pond, taking nutrients out of the water with plants, adding bacteria to the water to aid decomposition, and providing aeration through continual water flow and mechanical aeration, we can do our part to get our ponds ecosystem balanced. Once balance has been achieved, the pond will care for itself with very little human input.
Is your pond 6 ft. deep or deeper? Do your fish seem to be gasping for oxygen at the surface of the pond? Is there a lot of algae in your pond? Is it lifeless and stagnate? If you can answer “yes” to any of these questions, please read on. You have insufficient oxygen levels in your pond, and you will struggle to control algae in your large pond.
Ponds that are deeper than 6 ft. are often unable to produce enough oxygen at those depths. This lack of oxygen will lead to thick nutrient layers on the pond bottom. These nutrients will encourage more algae growth. The human’s knee-jerk reaction is to add chemical algae killers, which simply exacerbates the problem more than we even realize.
Algae control is essential for maintaining a healthy pond. Algae blooms may discolor water, further reduce pond oxygen, and can asphyxiate other life forms if present in significant quantities. Excessive algae growth typically signifies water problems and can make the water unsuitable for swimming, fish, and other animals.
Nutrient Pollution
Excessive nutrient pollution such as potassium, carbon, phosphorous, and nitrogen can originate from decomposing lawn clippings, fertilizer, septic systems, and farm runoff. For The most part, when you see a pond with an excessive algae bloom, it is the fault of the humans around the pond, not the pond. The pond is simply reacting to the conditions we have subjected it to.
A pond’s health is all dependent on the ecosystem and the circle of life. When we disrupt this balance, a pond’s condition can deteriorate rapidly.
Low Oxygen Levels
The bottom of the pond runs low on oxygen first. The decomposition of the debris on the pond bottom depends significantly on the oxygen levels at that depth. The absence of oxygen kills the bottom-dwelling animals (worms, snails, mussels, etc.) and aerobic bacteria that help keep the pond clean. The loss of these tiny pond helpers will significantly reduce the pond’s ability to clean itself.
Nutrients such as dead algae, grass clippings, leaves, plant debris, and animal waste fall to the bottom of the pond continually, so if the process of decomposition becomes interrupted by lack of oxygen or chemical treatments, the pond water quality can deteriorate quickly. This ever-thickening layer of nutrients will be the food for future algae blooms.
How to Increase Oxygen Levels
The best thing that we can do for a larger pond is to provide aeration. There are two types of aeration systems; bottom aeration and surface aeration.
Surface Aeration
Surface aeration is just like it sounds. It is usually a floating electrical water pump that shoots water into the air. This water shooting into the air picks up oxygen and falls back into the pond. The action of this water flying up into the air and landing back in the pond will typically effectively circulate the top three or four feet of your pond.
Bottom Aeration
Bottom aeration is, again, just like it sounds. We place an electric air pump near the pond, and we pump air down to the bottom of the pond using weighted air lines. At the bottom of the pond, the air is pushed through perforated membranes of one type or another. These membranes are called diffusers. The diffusers create tiny little air bubbles that add oxygen to the bottom of the pond and circulate the entire body of water. This is very similar to the bubbles coming up from the bottom of a fish tank—the same concept.
One bottom aerator will create a circular flow of water in the pond as the air bubbles rush to the surface carrying the colder deep water to the top, which causes the warmer topwater to flow toward the bottom. The deeper the pond, the wider the water turnover area will be. A shallow, long pond will require more diffusers.
This continual turning of the water column by pushing air to the bottom of the pond will help keep the oxygen levels high on the pond’s bottom. ThisThis will help all of the bottom-dwelling animals and bacteria thrive, allowing them to be more efficient at decomposing and consuming our pond muck, which will help starve the algae of the nutrients it needs.
One note of caution would be that if you install a bottom aerator in a deep old pond full of muck, the aeration will turn over so much water and carry so much of the muck into the water column that it can kill fish and other pond animals. When installing that new aerator, only run it for a few hours a day for the first week or so and then gradually increase the run time until you can safely run it 24/7.
Prevent Nutrients from Entering
Do everything that you can to eliminate runoff into your pond. The less runoff that enters the pond, the less nutrients it will carry. Of course, many ponds are strictly runoff ponds, so eliminating the runoff would be a real problem.
To reduce the amount of nutrients entering a runoff pond, make sure to maintain a dense border of plant material around the outside of the pond. The more plants that the runoff water runs through, the cleaner it will be when it reaches the pond.
If paved areas or a valley run into your pond, it is a good idea to provide plant-filled settling areas where sediment can settle out of the runoff and nutrients can be kept out of the pond. Fast-moving water will carry many nutrients and heavy sediment loads, so it is a good idea to slow it down as much as possible.
Make sure to minimize any fertilizer sources, lawn clippings, leaves, twigs, road salt, or any other chemical that may enter your pond. You can assume that everything uphill from your pond will end up in the pond, so use your best judgment and be careful.
Beneficial Bacteria
There are many different strains of beneficial bacteria that can be added to your water. There are many liquid bacteria applications that are well suited to smaller ponds and weekly or monthly maintenance, but for larger, deeper ponds, once you get your aeration system working, you will speed the decomposition process by adding more decomposers (bacteria) to the bottom. Look for sinking bacteria tablets such as Muck Buster or Muck off, which will sink to the bottom and give your decomposers a helping hand.
Whatever product you buy, make sure that it is entirely natural and chemical-free. Just because a product may be labeled safe for fish does not mean that it is safe for your pond. You only want completely chemical-free products.
With a natural bacteria product, you can never add too much, as the bacteria will be put to good work until the muck is so decomposed that there isn’t enough to support the bacteria levels. At this point, the bacteria will simply die off and be consumed by other water dwellers.
Plants
A straightforward and long-term solution to help keep your water clean is plants. Lotus and lilies reduce direct sunlight and provide shade, which helps control algae’s growth. Submerged plants such as hornwort, parrot’s feather, and anacharis release oxygen into the water and compete for nutrients with the algae. All marginal aquatic plants such as cattails, rushes, iris, reeds, etc., will compete for the same nutrients that the algae need to thrive.
A Problem With Plants
The more beautiful plants we have in our pond, the fewer algae we will have. One trouble with this in large unlined ponds is that these marginal aquatic plants can really take hold and will often spread and overwhelm a pond in a number of years.
We need the plantings in our ponds to compete with the algae for the nutrients to keep the algae in check, but we don’t want them to overgrow the pond. Often, this dilemma leads people to spray their pond with herbicides to kill off the plants. This leads them into a vicious circle of chemical use and algae bloom, as every time they use chemicals, they are killing off beneficial pond life, and every dead clump of plant roots is now acting as fertilizer for the next algae bloom. This is a never-ending, terrible situation.
A Few Solutions
So what can we do? If you have pond plants overtaking your pond, the best solution might be to excavate or dredge them out. This will remove the root mass and give you a fresh start.
Once you take care of that, you will be left with a pond that needs plants. There are two ways to solve this problem that have proven very effective.
Floating Plant Islands
Floating plant islands can be purchased or built yourself. The composition of the island isn’t as crucial as its function. It must be constructed of a material that will float, supporting plant growth and letting the roots grow through into the water. Most commercially available plant islands are made from recycled plastic and are a fibrous mat that is very buoyant and very porous. This allows the island to support a significant amount of weight and allows the plant roots to hang down into the water.
These floating plant islands mimic the floating bogs found in nature. The effectiveness lies in the fact that the plant’s roots are hanging into the water, soaking up nutrients. The mat is just floatation; you don’t need to add soil because the entire point is to have the plants take nutrients from the water.
The larger your pond is, the more coverage you will want. These islands are ideal. You get the benefits of plants in your pond without the disadvantage of having the plants spread throughout the pond. The islands are usually roped to the shore in two places to keep them out in the pond or anchored to the pond’s bottom.
Foliage Removal
For the ultimate nutrient removal, you can cut the foliage from the plants at the end of the season and dispose of them so that the decaying plant material doesn’t add nutrients back into the pond.
Floating islands are increasing in popularity to improve water quality and provide an attractive focal point in the pond. Plants grow remarkably well on a floating island. The same vegetation planted on the shoreline near an island doesn’t grow nearly as well. Floating island plants grow bigger and healthier than plants along the shoreline.
Growing Wild
If you prefer to let your floating island grow wild, try a native garden. Depending on where you live, there may be local sources for plants and flowers. Your local garden center can help point you in the right direction. These don’t need to be all aquatic plants! Depending on the type of island you install or build, you may be able to plant terrestrial plants that sit high enough to do just fine. Just don’t pick plants that like dry soil. They need to like it a little wet. Choose plants that attract birds, bees, butterflies, and other species.
You can do whatever you’d like with these islands. Get creative. As long as plants grow on them and roots hang into the water, they help control your algae and improve water quality. You can plant the island to complement the existing landscape, grow a floating flower garden, zen garden, or create a specialty island of your design.
No green thumb is required to grow an edible floating island. Grow any edible plant in your floating garden. Choose from edibles such as fresh herbs, fruits, vegetables, salad greens, or flowers. Planting it is simple and provides the perfect environment for natural and rapid plant growth with no pesticides or herbicides.
Floating Treatment Wetland or FTWs
FTW’s are very similar to standard floating islands but are typically larger and planted more diversely to allow for better habitat for other animals. Are you looking for a natural way to cleanse your pond and a safe alternative habitat solution? The FTW may be your solution.
FTW’s can be created to create habitat for waterfowl nesting, add shoreline protection, improve fish spawning, or greywater or stormwater treatment. There are many ways to make a beautiful and useful plant island. These are typically used in a larger, more commercial setting where greater stability and biodiversity are required.
The islands come in many shapes and sizes. The most common shapes are kidney, rectangular, or square. The islands can be joined together to make a larger floating island. The islands also come in circle shapes but are not as cost-effective as the other shapes.
The plants to use on your floating island will depend on the benefits you want to achieve from your island. Do you wish to beautify your pond, reduce algae, create a nesting island? Benefits such as nutrient removal, enhancement of habitat, the attraction of invertebrates, butterflies, or dragonflies can all be possible with one plant island, or you can create several different islands for differing effects.
The wetland filter can be planted thick with aquatic plants. The water getting pumped through the plant roots will allow the plants to absorb large amounts of nutrients to help control the algae in your pond. Aquatic plants seem to absorb more nutrients and grow more quickly when in moving water, so the wetland filter creates super-charged aquatic plants.
Wetlands also help clean your water by helping to remove ammonia and heavy metals from your water and providing an excellent place for sediment to settle out of the water column. Once again, to maximize water quality effects, the foliage can be harvested at the end of the season so that nutrients and removed toxins don’t re-enter the water.
Understanding Algae and How to Control it in Your Large Pond
Many pond owners have a problem with algae but do not understand what they are and how they grow.
While most people don’t consider algae to be plants because they don’t have stems or leaves, they are very simple, primitive plants that use the process of photosynthesis, just like other plants, to take energy from the sun and combine water and carbon dioxide to form sugars for energy and growth. Algae also produce oxygen like other plants and absorb oxygen when there is no sunlight.
There are two common forms of pond algae.
String algae, also known as hair algae, is a filamentous species that grow in long strands, adhering to rocks and waterfalls. They will eventually tangle together to form thick, unsightly mats that can double their weight within 24 hours.
Green water algae are single-celled organisms that remain suspended in water. They are so tiny they can pass through even the finest filter. If there is plenty of sunlight and nutrients in the water, up to five million cells per milliliter of algae can be in the pond water.
Balance is the Answer
Balance is the best when it comes to controlling algae. No natural pond is ever algae-free, but it can be kept in check in a balanced environment. Understanding how algae grow is a good start. Understanding that chemicals and sterilizing gadgets are never the answer is an even better start.
The realization that it is our job to simulate mother nature’s ways of creating balance and harmony in our man-made ponds is the step that many pond owners never grasp. We should never fight with nature; we should step back, learn from nature and figure out how to allow nature to help us.
It sounds simple, yet it is so very hard for some. Patience and understanding is the answer. We often want a quick fix, so we grab a chemical, dump it in, kill the algae and think we are done. We don’t realize the headache and never-ending battle that we have just started. Using Mother Nature’s way through the addition of plants and bacteria coupled with some mechanical aeration, we can create a simple, long-lasting solution that will cost much less long term both financially and environmentally.
Don’t Be Fooled
Natural pond balance works for the control of algae. Don’t let anyone tell you otherwise. Most pond companies will promote needless monthly chemical applications to maintain a pond. They are merely selling a product that will poison the water. If it is done the natural way, the pond will eventually do very well independently with no help from us.
When we use chemicals, it is a vicious cycle of killing algae with chemicals, and the dead algae go to the bottom, creating more nutrients for the next algae bloom when the chemicals wear off. This is what makes most natural bottomed retention ponds such a nightmare for their owners – chemicals and thick muck on the bottom of the pond. Job security for the chemical application companies for sure!
Using plant islands and wetland filters, we are mimicking the way that nature takes care of the natural ponds and lakes on this earth. Working with mother nature is always easier than working against her.
A Pond is a Pond – Treat it Right
Whether you have a large backyard pond or are the manager of a retention pond or golf course pond, your hardships are often the same. You want clean and clear water that is not thick with algae. If you have been trying to maintain this pond for a while, you are likely frustrated by the lack of simple fixes and the fact that most professionals will tell you that they need to apply chemicals weekly or monthly for eternity to control the algae.
I’m here to tell you that they are wrong, very wrong. There are many simple and natural solutions to your pond troubles, and once you get your pond balanced and functioning as it should, your maintenance headaches will be eliminated. Treat it right and it will do the rest.
Nutrient pollution and sunlight cause the overgrowth of algae. High nutrient levels and other chemical pollutants can be a severe and critical burden for many of our natural waterways, especially in the more industrialized parts of the world. Floating plant islands are a natural, economical, and effective way to treat all types of water. Plants chosen for the plant islands should be based on the plants’ phytoremediation abilities and matched to the cleaning needs of the water.
According to the EPA, nutrient pollution is one of the most costly and pervasive environmental problems in the country. The use of artificial floating plant islands began as a natural way to treat wastewater about 40 years ago in North America and is currently a popular method used in Asia.
The floating plant island’s design is to provide a porous yet buoyant floating surface that will support the weight of the growing plants and allow the roots to pass through the island to hang down into the water. There are many different designs, but they all work about the same.
The islands can be placed linked together as a group or individually on the water’s surface. Either way, the islands do a great job of filtering water, and they look like a beautiful island of plants once they have grown in.
They are ideal for ponds with no planting shelves, ponds that are too deep to grow aquatic marginals, and any natural bottomed body of water where it is not practical or desired to plant into the shoreline.
How do Floating Plant Islands Help?
The islands remove nutrients from the water using the plants on top of them. The plants absorb the nutrients for growth, while the underwater root systems trap solids. Bacteria can form on the plants and floating structures that remove the nutrients using chemical processes.
Floating Treatment Wetlands
Some floating plant islands are also called floating treatment wetlands (FTWs), or human-made floating wetlands. These FTW’s are typically more than just a simple flat plant island but are instead crafted with more flotation to allow for a more varied island structure allowing for a more diverse assortment of plants and animals to thrive. As with any natural ecosystem, diversity is king.
Floating treatment wetlands, being larger, more diverse, and more buoyant, can be used to treat bigger problems in much more harsh environments than a standard plant island can. In addition to treating water, the FTW’s can also be used to control water flow and help protect shorelines from erosion.
The porous, fine material allows water in, prevents soil from entering the pond, and protects plants from fish. It is constructed to float at the pond’s surface and provides attractive options for showcasing your favorite aquatic plants.
Floating islands create a habitat on the water, which acts as a purifier. Plant growth is encouraged both below and above the waterline, allowing for wetland and terrestrial plants to grow. This enables a variety of plant species to purify the water in ponds, canals, and lakes.
Pick the size of the island you want
floating plant islands
Floating islands come in all shapes and sizes. The size you choose should depend on the types and number of plants you want on the island. The bigger the plant mass, the bigger the island you will need.
Installation of a Floating Island
strange floating plant island
You don’t need specialized equipment to install a plant island, but a small boat might be helpful, depending on the size of your pond. Plant the islands on the shore and push them into the water. What could be easier? Most floating plant islands, both large and small, are anchored to the bottom of the body of water, but sometimes they are tethered to the shore or each other to keep them in place.
A floating island is a simple way to add aquatic plants to your pond for beauty and the benefits they provide. The islands can be constructed in many different ways, but the one thing they all have in common is that they must float, and they must allow the plant roots to hang through into the water.
Choose a location in your pond.
Where to put it? That is your choice entirely. It is typically placed toward the middle of the pond, but as long as it is in the water, it is fine. More water flow is better; the plants will grow more quickly and remove more nutrients in moving water than still water. Enjoy its beauty! It is a living and cleaning piece of art — enjoy it.
Planting a Floating Island
Planting a floating island is easy. You can make it as simple or ornate as you desire. Just put the plants into the fibrous material of the island. Once in the water, the plant roots will quickly grow into the water. If planting terrestrial plants, you will likely need a bit of soil on top of the island. If planting only aquatic plants, no soil is required.
Here are a few guidelines to get started
Choose moisture-loving plants
The plants you choose must tolerate moist soil and shallow water conditions. You can certainly add terrestrial plants to the island, but they will need to be higher out of the water than the aquatic plants.
The only aquatic plants that will not work on an island are ones needing deep water, such as water lilies. Also, be aware that small plant islands with tall plants may tend to roll over, so plan accordingly.
For aesthetic appeal, place the focal-point, taller plants in the middle and surround them with ground cover plants along the edges. Plants that creep and spill over the sides work exceptionally well for floating islands because they hide the island’s foam edges.
Here are some suggestions of the ground covers that can be used.
Blue Creeping Mazus
Blue Moneywort
Creeping Jenny
Golden Creeping Jenny
Red Rotala
Variegated, Crystal Confetti Pennywort
Water Pennywort
White Creeping Mazus
Aquatic mint
Aquatic celery
Here are some suggestions for the taller plants you can use
Blue-Eyed Grass
Carolina Yellow Jacket Pitcher Plant
Chameleon Plant
Dana’s Delight Pitcher Plant
Horsetail
Mini Horsetail, Dwarf Scouring Rush
Red-Stemmed Parrot Feather
Society Garlic
Star Grass
Variegated Society Garlic
Yellow-Eyed Grass
Reeds
Rushes
Arrowhead
The Hard Working Plants
huge water lillies
The plants and their roots have a critical role to play. The long roots are doing two things. They slow down the water movement, help with settling, and the bacteria and microbes get stuck in the sticky biofilm on the roots to clean the water. There are also many benefits to the food chain. Many forms of pond life can make their home in the roots and on top of the island. With time, the plants will all grow together, and other plants are sure to seed themselves into your island, so make sure to use an island with plenty of floatation.
For the ultimate in nutrient and pollution removal from the body of water, the foliage of the plants on the island should be harvested at the end of every season to avoid having them die back and decompose back into the pond water. Roots do not need cutting, but allowing some of the plants’ foliage to die and disintegrate on the island will help begin the natural soil-building process to enrich the island for many years.
Six Midwest Flowers that are Perfect
Here are six Midwest flowers that are perfect for floating plant islands. Multiple species of native plants should be planted to attract diverse birds and insects. Scientific names have been included to help locate them at a nursery if needed.
Marsh Hibiscus – Hibiscus Laevis
This northern native plant is also known as Rose Mallow. It grows back every year in the same location. It can grow up to five feet and is a woody bush, which blooms from July to September. It has sturdy wood stems, makes an excellent center anchor for the island, and offers winter habitat if not trimmed.
Marsh Marigolds – Caltha Palustris
These are short mounding marigolds that thrive in moist areas. They bloom in early May and can, on occasion, have a few flowers blooming again late in the season. The leaves are dark green.
Obedient Plant – Physostegia Virginiana
These plants are common in wetlands and along shorelines and can spread quickly and take over less aggressive plants.
Rose Milkwood – Asclepias Incarnata
Butterflies love this tall, straight flower. It varies in height from three to five feet, blooming from mid-to-late summer. It is commonly found along undisturbed marshy areas.
Sweet Flag – Acorus Americanus
This yellow and green perennial plant looks like a bigger version of the iris but does not have a standard flower. It has a spathe, which encloses a flower cluster. The sweet flag was a favorite among Native American tribes for use as a medicinal resource. It was also used for ceremonies and trade. It gives off a lovely fragrance when the leaves are broken.
Wild Iris — Versicolor Iris
An iris is one of the first flowers to bloom in the spring of the year. The blue and purple flowers fade quickly, but the plant excels in providing a lovely backdrop for shorter summer flowers. Wild iris love to be wet, so they are perfect on a floating island with constant water access.
Do not introduce species onto the island that is non-native or invasive.
After several years, nature will become the gardener, so don’t sweat it when new plants show up.
The islands can stay in the water year-round. Repeated freezing and thawing cycles do not harm them.
Plant islands can be excellent nesting habitat for birds. If you don’t want aquatic birds nesting on your island, you may want to install light fencing around the perimeter.
Avoid flowering plants that are “tasty,” such as lilies or nasturtium, as they may attract muskrats.
The Effectiveness of Floating Plant Islands in Filtering Water
Floating plant islands are great at cleaning up wastewater because they filter out metals, pathogens, nutrients, and other water contaminants. Why invest billions of dollars in building new wastewater treatment facilities when there is a natural and environmentally-friendly way to solve the problem. Plus, it is a low-cost and highly effective way to deal with nutrient pollution in smaller ponds without harmful chemicals.
These plant islands are like “floating water treatment plants,” combining the greenery you would see in a traditional wetland with some human-made technology to keep it afloat.
There is a sticky biofilm that will form on the island and the roots below the island. It grabs microbes and bacteria which colonize to disintegrate the pollutants, and as they are at the beginning of the food chain, they will be fed on by fish and other organisms. The islands provide diverse habitats above, inside, and below the water.
The floating island provides a place for bacteria and microbes to colonize by adding a tremendous amount of surface area and an excellent place for them to flourish. While they grow, they are active and moving, which is when the pollutants in the water are breaking down. The dirtier the water is, the more active the microbes are, the more water is being cleaned.
Floating islands are an easy way for us to mimic the wetlands and bogs that have been cleaning the earth’s water since time began.
Why Are Wetlands and Bogs Important?
Marshes, swamps, and other water-soaked lands link organisms in water and land in a way that permits them to co-exist naturally. As water moves through the plants’ roots, it is naturally and efficiently cleaned by the plants and the multitude of organisms that thrive in their root masses. It is unfortunate, but wetlands are being replaced rapidly for agricultural or urban development, depriving the earth and its waters of many countless acres of filtration that have for so long protected our precious groundwater and aquifers.
Here are a few facts about the importance of wetlands.
Wetlands are similar to human kidneys. Our kidneys extract waste from the blood and balance bodily fluids. The wetlands can clean the water that flows through them, mitigate large flood events, and recharge the underground aquifers.
Wetlands also provide fisheries and timber resources, protect coastal communities from extreme weather events such as hurricanes and typhoons, and provide a habitat for biodiversity.
Wetlands can lessen climate change. Coastal wetlands such as mangrove forests store large quantities of blue carbon in the vegetation. “Blue carbon” is stored naturally by marine and coastal ecosystems. These ecosystems hold a lot of carbon. An area of a mangrove forest can store up to ten times as much carbon as a land-based forest of the same size. It is vital to conserve and protect the blue carbon because its release of carbon dioxide (CO2) into the atmosphere is a significant cause of climate change.
Wetlands are a habitat for biodiversity as the species found there are some of the most unique in the world. They have evolved specifically to survive in these hydrologically changing ecosystems. Muskrats, alligators, nutrias, crocodiles, fish species, and hundreds of birds such as geese, mallards, and herons are found in wetlands. There are more than 800 protected migratory birds in the United States, and more than half of them rely on the wetlands.
The vegetation located in wetlands has evolved to survive in seasonal flooded and saline conditions, making it unique as well. Examples of this are mangrove species in coastal wetlands and cattails in freshwater wetlands.
Threats to the wetlands continue as many of them are being drained, destroyed, and replaced with commercial, residential, urban, or agricultural development. The destruction of the wetlands negatively impacts millions of people dependent on the ecosystem’s services.
Wetlands are known to clean water. Thick vegetation traps excess nutrients and heavy pollutants and keeps waterways free and clear. Unfortunately, many rivers and lakes no longer have wetlands. They are the first to be eliminated when planners need more real estate areas to develop.
Wetlands improve water quality in stormwater runoff and manage watershed nutrients. They are beneficial to the treatment of wastewater and other industrial contaminants. Wetlands rely on a natural process to filter water biologically. It passes through permeable bottom soils and shallow areas of dense aquatic vegetation.
The nutrients are removed by the uptake of microbes and plants, assimilated, absorbed into inorganic and organic sediments, then converted into gas by dissolving. The aquatic plants above and below the water take up these elements and remove them from the sediment and water column into the biomass or plant material.
How These Floating Plant Islands Can Help Ponds
The two most significant benefits are improved water quality and the diverse habitat. The floating wetlands reduce algae by cycling nitrogen and phosphorus. They reduce suspended solids which are the cause of cloudy water.
The second main benefit of creating diverse habitat is “above the island,” “on the island,” and “below the island.” Frogs and turtles are attracted to the surface of the island. Plants appealing to pollinators, such as butterflies, bees, beetles, flies, bumblebees, and honeybees, should be planted. For example, if you live in an area where monarch butterflies are plentiful, plant swamp milkweed. Other plants that are important for the birds and bees will help them with a nutritional plant they may not encounter in an individual’s garden.
Pond plants provide oxygen enabling fish and other animals such as aquatic insects and other small creatures to live in the pond by providing food and shelter. In larger water bodies, aquatic plants help reduce wave action, preventing erosion.
There are numerous organisms living in the porous holes of the island. The organisms, or macroinvertebrates, are essential. The island will double in weight during the first year because so many of them and other animal species live on the island.
Shoreline Protection
Many people value islands for the protection of the shoreline. For example, in Gulf areas, floating islands offer shoreline protection to help restore the marshes by reducing the wave chop.
They can also be used for soft-scaping and beautification. In urban areas where there are metal walls along some waterways, the floating islands provide a natural habitat and make the waterway more attractive.
Aeration
Adding aeration below floating islands is an excellent way to improve your floating island’s efficiency. Lake bottom aeration below the island provides an oxygenated environment where aerobic bacteria thrive. The biofilm, which forms under the islands’ surface, colonizes the biofilter and becomes the habitat for billions of beneficial bacteria. The bacteria consume excess nutrients in the water, creating the water’s perfect treatment. More oxygen and more water movement will equal more efficiency and more water clean-up.
Natural Pond Balance Works
lotus flower
Most people do not have the patience to wait for nature to take its course. That is why so many companies promote the use of chemical applications for pond maintenance. The products they sell are poisoning our water. It becomes a vicious cycle of killing the algae with chemicals. The dead algae go to the bottom, creating more nutrients for the next algae bloom when the chemicals wear off. This is why most natural bottomed retention ponds are a nightmare for their owners – chemicals and thick sludge stay on the bottom of the pond.
But done the natural way, the pond eventually does very well on its own. And without our help!
Install a plant island in your pond today and take one massive step toward maintaining your backyard pond, retention pond, or golf course pond naturally.
There are hundreds of types of pond algae. The two most common are string algae which look like long green hair, and planktonic algae, which looks like green pea soup. Many pond owners get very frustrated when trying to control algae. I often get asked, “How can I kill the algae in my pond?” This is the wrong question. They should be asking, “How can I control the algae in my small pond?” For this question, I have an answer.
A Common Misconception
A common misconception is that algae are bad for a pond. Only during a very out of control and heavy bloom is algae bad for a pond or fish. This is rare in a small backyard pond. Usually, the algae are irritating to the pond owner but not necessarily bad for the pond. All-natural ponds will have some algae. This is a sign of a healthy pond. We need to control the algae by creating balance in our ponds.
Types of Pond Algae
String algae or filamentous algae will form mats that float on the pond’s surface, resembling wet wool. It will also grow along the pond’s bottom or edges where there isn’t much water circulation. Many pond owners refer to this kind of algae as “pond scum.”
Planktonic algae are floating microscopic plants that are usually suspended in the first couple feet of water, making the water look green and “pea soupy.” This is the stuff that might prevent you from seeing your fish.
How to Control Algae
Before you can determine how to control algae, you need to understand what makes it grow.
Pond algae need two things to grow: nutrients and sunlight. By controlling these two things, we can maintain our pond’s balance, which will control the algae. Sounds simple enough, right?
Sunlight
You can block the sunlight from the pond by using an aquatic sun blocker or pond dye, but this is unnatural and looks ridiculous. It is much better and cheaper long term to plant a few water lilies in your pond to shade the water.
Prevent Nutrients from Entering
You can prevent nutrients from entering your small pond by keeping leaves, debris, and runoff out of your pond. Some people go overboard with this. While it’s great to keep excess debris out of your pond, I’m guessing that you don’t have a bunch of time for this activity. Some people are out skimming leaves from their pond daily. I never do this.
A well-balanced pond will be able to deal with a few leaves; what messes up pond balance is fertilizer runoff. The worst algae blooms that I have seen were the result of runoff carrying lawn fertilizer into the pond or lawn fertilizer getting into the pond during application.
Chemical lawn fertilizers are very concentrated, and they can easily throw a pond out of balance. Another very common way to accidentally fertilize your pond is by blowing grass clippings into it. If you pay someone to fertilize and mow your lawn, take some time to watch them as they work. Make sure that they aren’t adding to your pond nutrients.
Remove the Existing Nutrients
All ponds have some debris in them. Adding beneficial bacteria to our ponds will help break down any debris that is already in the pond. By maintaining high levels of bacteria, we can ensure that we don’t get any debris build-up in the pond.
Add Oxygen
Low oxygen levels in our water will slow down the decomposition of the debris. High oxygen levels speed up decomposition and allow more beneficial bacteria to survive and help us out. You can raise the oxygen levels in your water by installing a waterfall, a fountain, or a bottom aeration system.
Add Plants
Plants are our biggest pond helpers. The pretty plants in our ponds are competing with the algae for the nutrients in our pond, so the more plants we have in the pond, the fewer nutrients will be available for algae. Floating plants, submerged plants, and marginal aquatic plants can all do their part to help balance our ponds.
Most garden ponds do not have enough plants in them to handle all the nutrients in the water. Planting more plants will help reduce algae, But what if we could install something to supercharge the removal of nutrients?
Install a Wetland Filter
Upflow wetland filters mimic the natural wetlands that filter all of the earth’s water. By installing a wetland filter in your pond system, you provide your pond with the absolute best filtration available. A wetland filter can be planted with many aquatic plants, and these aquatic plants that are in the wetland filter with pond water getting pushed through their roots will grow more quickly and remove more nutrients than plants that are growing in the pond.
When barley straw decomposes in water, it releases a natural toxin that slows and discourages algae growth. Put a small bale of barley straw in your small pond, and you will help control the algae cheaply and naturally. The barley should be placed somewhere near the surface or below a waterfall in the pond. Once again, more oxygen will help the barley decompose more quickly. Moving water is our friend.
Add Fish
Many people think fish are an option when you own a pond. I consider fish to be a vital part of pond balance. Your fishy friends will spend their days rooting around through the gravel on the bottom of your pond, stirring things up and eating the algae. Be careful not to feed your fish too often; hungry fish make for a clean pond. Any fish food you toss in the pond that doesn’t get eaten becomes fertilizer for algae.
Never, Ever Add Chemicals
Chemical products designed to kill algae are never a good idea. Killing algae is not the answer; controlling it naturally is. Any chemical killers that get into your pond water kill off beneficial bacteria and beneficial microscopic pond dwellers that help keep our pond balanced.
Killing the algae results in dead algae, dead bacteria, and dead pond creatures piling up at the bottom of the pond, just waiting to be fertilizer for the next algae bloom as soon as the chemicals wear off. It is a never-ending vicious circle, don’t do it.
Wrapping it Up
If we understand that our small backyard ponds are natural ecosystems and that they will take care of themselves if they are correctly balanced, we can understand how to control our algae.
If we have heavy algae blooms, we have too many nutrients in our pond. Killing algae will only make it worse. We need to eliminate the excess nutrients, not the algae.
We can do this by keeping the nutrients out of the water or by removing nutrients from the water.
Keep debris and runoff out and add plants, bacteria, and fish to promote balance. Balance will take a bit of time and patience to achieve, but everything gets much easier once we achieve this balance.
Working with nature is always the easy way. Working against nature will only bring us trouble.
Keep it simple and be a part of the solution, not the problem!
Every backyard pond that you have ever seen is a functioning ecosystem. Just as all plants and animals out of the water are part of the natural ecosystem, all of the life below the water is also part of its own little ecosystem. An ecosystem is a dynamic, functional unit comprised of consumers, producers, and decomposers. One portion could not survive without the other, so the well-being of the whole will be reflected in the individual’s well-being.
Garden ponds were rare not so long ago. They are now considered to be an essential part of many backyard gardens. They genuinely transform a backyard, no matter the size of the pond. Dragonflies, fish, frogs, and lovely plants are all part of the beauty that comes with a backyard pond. It can be as grand or as simple as you would like.
The addition of a waterfall to the pond will create a beautiful visual and auditory display. It will also help improve the pond ecosystem by providing vital water movement and oxygen. You will also find that living creatures such as frogs, snakes, birds, turtles, rabbits, mice, chipmunks, and squirrels will all appreciate having a fresh water source nearby.
A backyard pond will include the following:
Rubber Pond Liner
Most small backyard ecosystem ponds are lined. Pond liner is used to retain water in a garden pond, stream, and waterfall. 45 mil, EPDM Rubber the most common pond liner used because of its flexibility to conform to any shape and durability to withstand many years of service. The rubber liner is laid into a previously excavated hole, and the edges of the rubber are tucked in or hidden above the pond’s high water line.
I would always recommend installing underlayment under the rubber to help protect it from sharp sticks and stones. Underlayment is cheap; rubber is not. EPDM pond liner will last indefinitely if protected from the elements. Sunlight is the most destructive force for rubber, so protecting the liner from the sun by covering it with rocks, gravel, and plants is your best bet.
Piping for Your Pond
I would always recommend using flexible PVC piping as it is easy to work with, it can be bent to create curves, and it is reasonably resilient to the freeze and thaw that occurs in many climates. The pipe must be back-pitched to allow for the water to drain out when the pump is off to avoid freezing when full of water.
Pump
You will need a pump to move the water in your pond; stagnant water does not make for a thriving ecosystem. Your pump should be chosen based on efficiency and desired water flow. This site has much good information on pond construction. They say you should select a pump capable of turning over the pond water volume once each hour.
Filtration
Having a wetland filtration system for your pond will allow the water to be filtered, the suspended solids to settle out, and help remove toxins and nutrients from the pond water, which will help create a healthy pond ecosystem. There are hundreds of man-made filter boxes and systems on the market, but they all pale in comparison to the wetland filter and, for the most part, are not worth the money.
So How Does a Backyard Pond Ecosystem Work?
As we mentioned, the pond ecosystem is made up of producers, consumers, and decomposers. Let’s talk a bit about each of these groups and what they do for our backyard pond ecosystem.
The Producers
the producers
The biggest producers in our backyard pond ecosystem are the plants. Just like plants play the most critical role in our above water ecosystem, they also play the most important role in your backyard pond ecosystem. They collect their energy from the sun and use photosynthesis to convert carbon dioxide and water to organic compounds and oxygen. These plants, in turn, require phosphorous and nutrients to survive.
While algae aren’t technically classified as a plant because it doesn’t have stems and leaves, it is a plant-like organism that carries on the process of photosynthesis. In fact, there have been some scientists who estimate that algae produce half of the earth’s oxygen. So, the next time that you see algae bloom in your pond, you can smile, knowing that your pond is helping to oxygenate our earth.
The main reason that you are getting these algae blooms in your pond is because of nutrient pollution. Nutrient pollution is typically caused by fertilization, runoff, and animal wastes. When we get an algae bloom, we should look in the mirror for the cause because it is us more often than not. People often think that algae blooms are bad. The reality is that they are likely just a symptom of something that humans have done to offset nature’s balance. With backyard ponds, lawn fertilizers are often the worst culprits.
The pretty aquatic plants and the algae in our ponds compete for the same nutrients. The most effective way to control algae growth in your backyard pond and maintain clear, healthy pond water is to incorporate many plants into the pond. More plants taking in nutrients means that there will be fewer nutrients available for algae.
Some plants are more effective than others at removing nutrients from a pond. An effective wetland filter filled with plants will help maintain good water quality by eliminating harmful ammonia from fish waste and decaying plants and allowing all of those plant roots to soak up the nutrients from your water.
These ultra-effective plants are known as “clear water plants” because they will beat the algae to the water’s nutrients. These are fast-growing plants with high metabolic rates and extensive root systems to absorb nutrients. This makes them really good at soaking up phosphorous and nitrogen.
Here are some of these “clear water” plants.
Oxygenating Pond Plants These plants, such as hornwort and water thyme, are incredibly effective clear water plants because they feed through their roots and foliage. One bunch should be used for every three-square foot surface area of the pond for the best result. They also provide spawning areas for fish and provide shelter for baby fish.
Floating Pond Plants Water lettuce and water hyacinth are beneficial as filter plants because they are fast growers and heavy feeders. They will multiply quickly and take in many nutrients right up until the first frost when they will wilt and die. They block the sun and shade the pond competing with algae for nutrients. Like submerged plants, their root structure provides spawning areas for fish and shelter for babies. Duckweed, ivy duckweed, fairy moss, and floating fern are also effective clean water plants.
Variegated Water Celery Variegated water celery is a good, low-growing filter plant. If planted in a shallow gravel bed or a mesh planting basket, these plants thrive, producing thick roots. The variegated foliage is attractive in the spring when it has pink fringes.
Water Iris Water iris have beautiful flowers and stunning sword-like foliage. They are also very efficient filter plants. Like other marginal plants, they are best planted in shallow gravel beds or mesh baskets to spread their fibrous roots.
Watercress Watercress is a very vigorous plant with delicate white flowers. When the warm weather arrives, this low-growing plant will grow extremely fast, producing long white roots that are very efficient at sucking up nutrients from the water. Watercress prefers to grow in flowing water, making it perfect for streams and waterfalls. It is also suitable for your salad!
Pickerel Plant Having beautiful pink or blue flowers, pickerel plants are functional, clear water plants while also being decorative.
Taro Taro are tropical plants that produce huge leaves, some having beautiful patterns and colors. The “Black Magic” variety is a popular variety that has very dark purple, almost black, stems, and leaves. When the water gets warm, these are amazingly fast-growing, but if you are in the colder climates, the plants will die at the first sign of frost.
Water Lilies Water lilies are not considered filter plants, but they shade the water, which inhibits algae growth and keeps the pond water cooler. A well-thought-out garden pond should be 60-70% covered with plants. Water lilies are always a pond favorite as they can bloom all summer and come in a wide array of colors.
Caution
Be aware that many fast-growing aquatic plants are considered invasive, so check your state’s invasive plants list and be sure to keep these pond plants in the pond where they belong. Fast-growing plants in the pond are great for absorbing nutrients, but they can quickly take over garden beds out of the pond.
Consumers
the consumers
The consumers in your backyard pond ecosystem are all of the creepers, crawlers, and swimmers in your water. There are tiny little microscopic zooplankton; there are small little invertebrates (water beetles, snails, worms, pond skaters, etc.) and the larger vertebrates (fish, frogs, snakes, etc.). All of these consumers swim around-consuming each other as well as feeding on the plants and algae in our ponds.
Decomposers
decomposers
The bacteria and enzymes in your backyard pond ecosystem are the base for the animal food chain. Bacteria and enzymes decompose and consume any waste material from plants or animals that end up in your pond. Bacteria also become a food source for the consumers in your pond, which may, in turn, become food for the larger animals that come to your pond. All of these living organisms compete for the nutrients in your pond. The more nutrients that get taken up by these pond organisms, the less there is available for algae.
There are aerobic and anaerobic bacteria, each serving their own purpose in your pond, breaking down organic matter. Healthy quantities of bacteria and adequate oxygen levels will reduce the muck (organic sediment) on the pond bottom. This muck layer on the bottom of your pond can be thought of as fertilizer as it contains phosphorous and nitrogen, both of which contribute to algae growth.
Removing this muck using natural bacteria products will improve water clarity and reduce the amount of phosphorus and nitrogen available to grow algae. If you spend time in your pond, you will appreciate the lack of slimy muck on the pond’s bottom.
Enzymes are required for life on earth. Just like we can’t exist without oxygen or water, we can’t exist without enzymes. Enzymes are organic proteins that are made from amino acids. In nature, enzymes control the build-up and decomposition of necessary matter in animal organisms and vegetation.
All of this decomposition and breakdown being caused by the bacteria and enzymes won’t happen (or will at least be slowed dramatically) without oxygen. In eutrophic or aging ponds where aquatic plants and algae are a problem, there is usually too much organic waste and insufficient oxygen.
This is why water flow is so essential to a pond. The more water flow we give our ponds through waterfalls and bottom aeration, the more oxygen is present, and the more effective the bacteria and enzymes can be in breaking down the organic muck.
Here is The Ecosystem Circle
To summarize: Plants take in nutrients and give off oxygen, bacteria decomposes and consumes organic muck. Fish, water bugs, etc., eat whatever is smaller than them, including plants, and all waste and decomposing debris creates nutrients to feed the plants. There it is, one big circle!
Here is How We Humans Screw Up the Ecosystem
humans and the ecosystem
This circle of life can be easily disrupted. The typical, uneducated(on pond life) homeowner means well and wants a nice-looking pond, so they go to the local hardware store or search online for algae killer and find a hazardous chemical that will kill the algae. This product is touted as fish safe, so they think it is okay. Fish safe means that it shouldn’t kill your fish unless you apply too much. Sort of how radiation is “human safe.”
In reality, any of these man-made chemicals are hazardous and deadly to life in your pond. They may not kill the fish, but they do kill much of the other life and bacteria in your pond, along with the algae.
The homeowner dumps it in their pond, keeps their fingers crossed, and sure enough, the fish lived, and the algae died. They are happy, but they don’t realize that they just created a biological nightmare.
The chemicals killed much of the pond’s beneficial life, and the dead algae sank to the bottom. Now they have a layer of dead algae on top of a dead bunch of muck that has lower bacteria levels because of the chemicals. The algae layer now begins to rot slowly and robs the muck of whatever oxygen there was at the pond bottom. As it decomposes, the algae gives off nutrients which create a rich environment to feed the next algae bloom as soon as the chemicals wear off.
One week or so later, the homeowner is back buying more chemicals to start this process all over again.
We need to have patience, step back, and let our pond ecosystem take care of itself. Add beneficial bacteria, add more plants to the pond and wait for it to balance. Once in balance, your pond will take care of itself. That is what this ecosystem is all about.
Also, be aware that many companies out there are creating new gadgets every year that claim to help your pond. Chemicals, chemical injectors, ionizers, UV-sterilizers, sand filters, etc., are all products that are designed to empty your pocketbook but will not help your pond ecosystem. Only mother nature can do that!
Aquatic Wildlife
wildlife and water
Garden ponds add beauty and visual interest to a backyard landscape, but they can also benefit wildlife as a habitat. Ponds offer food sources, clean water for drinking or living, shelter, and nesting sites or materials for many types of wildlife, including butterflies and birds.
We, in turn, benefit from the ecosystem provided by the pond, with more mosquito-eating dragonflies and cleaner, oxygenated air.
Gradually sloping edges or ledges with short vertical drops on the edge of the pond will help many smaller birds, insects, and amphibians get in and out of the pond with ease or enable them to access the water for bathing or drinking.
Here are some things to consider that will benefit and attract wildlife to your backyard garden pond.
Moving water – the sound attracts wildlife and reduces breeding mosquitoes.
Perches and shelters provide areas for wildlife to rest, find food, offer nesting areas, or hide from the elements and predators. Pale-colored rocks can reflect the sun to warm dragonflies’ bodies and other insects.
Sun and shade – if possible, locate your pond so it receives both some sun and some shade part of the day. You will attract a wider variety of wildlife.
Significant water depth will prevent the pond from freezing all the way through during the winter. I would recommend a minimum of three feet deep. This is advantageous, so aquatic wildlife and plants can survive the winter. Aquatic wildlife can also hide from predators in deeper sections of the pond. It’s hard, but remember that predators need to live too. Losing some fish to predators only means that your pond is an active part of the larger ecosystem.
Avoid invasive animals or plants in your backyard pond. A seed, root, stem, or leaf, pest, or disease can spread at random, even into the containers of non-invasive aquatic plantings. Some invasive plants to avoid are:
Flowering rush
Brazilian elodea
Yellow flag iris
Eurasian watermilfoil
Plant a native garden close to your pond that will attract a diversity of wildlife to your yard, which will then find and use your new wildlife pond.
NEVER spray pesticides, herbicides, or insecticides near your pond or anywhere on your property. Our ecosystem depends on you to do your part to take care of it.
Conclusion
With a bit of patience and knowledge, we can easily have a beautiful, low-maintenance backyard pond with a fully functioning and balanced ecosystem. This pond will enliven your yard for the rest of your life and will benefit the lives of any animal that is lucky enough to live near it. Just have patience and let mother nature do the heavy lifting.
For many hundreds of years, barley straw has been used to control algae growth in ponds. There is no official documentation about when the use of barley straw for ponds first began. The story goes that an English farmer was traveling by wagon along his property. A few barley straw bales fell into an algae-ridden pond. This accident proved to be fortuitous for this farmer and others who made their livings from agriculture and farming.
Controlling algae in ponds with barley straw is becoming more common. Studies conducted in England in the 1990s found it to be effective for this purpose. Since that time, its use has spread throughout America by scientists trying to assess its effectiveness and pond owners looking for effective and easy ways to combat algae. Rye or other types of straw are not effective in combating algae.
Barley straw is helpful in controlling algae only and not effective against plants such as duckweed, pondweed, or watermilfoil.
You are probably wondering, “how does barley help my pond”? Let’s discuss what algae are, the problem it causes, and other information that will answer this question for you.
What are Algae?
Algae are microscopic, free-floating plants that comprise a vital part of water’s food cycle. They are fed upon by tiny creatures called zooplankton, an important food source for fish. Algae color the water brown or green. If the growth is not controlled, it can lead to noxious odors, nuisance surface scum, poor water clarity, and an overall reduction in the body of water’s recreational value.
Algae come in a variety of colors and shapes.
Chlorophyta – green algae
Chrysophyta – golden-brown algae
Euglenophyta – euglenoids
Phaeophyta – brown algae
Pyrrophyta – fire algae
Rhodophyta – red algae
Xanthophyta – yellow-green algae
A common form is “planktic,” single cells that float in the water and, when abundant, give it a soupy-green appearance. The form “filamentous” grows in hair-like strands forming mats on the water’s surface. While some algae forms have relatively complex shapes that may appear to be higher plants, they do not have roots or leaf veins.
Algae produce oxygen during the day through photosynthesis but stops at night. Algae continue to use oxygen at night, and a large population of algae in a pond can deplete the oxygen supply overnight. This will cause a low-oxygen situation that can be harmful or fatal to aquatic life. Large algae die-offs can also deplete oxygen levels. This is another reason why chemical pond treatments are so dangerous for fish.
Excessive levels of algae occur when phosphorus or other nutrients are in abundance. Take steps to reduce the amount of phosphorus entering a pond to control algae growth directly. Usually, this is accomplished by treating the pond or lake with compounds such as Cutrine Plus or copper sulfate. While these treatments may be useful for short-term control of algae, they are also toxic to food source organisms that are essential for fish, such as insect larvae and zooplankton. We would never suggest using such toxic chemicals in your pond.
Chemical applications are very hazardous to our environment, and they start a vicious cycle of application and re-application as their effectiveness subsides in a short time. The build-up over the long-term of copper in water sediments is an environmental threat and a health concern. It is preferable to use an eco-friendly method to control algae growth. There must be a safe and environmentally friendly way to prevent algae growth. Barley straw is the solution; harmful chemicals are not.
The Algae Growth Problem
Excessive algae growth is a common problem in ponds, and traditional chemical control methods are not advisable due to their adverse health effects and high cost. When applied at the proper time and correct amount, barley straw has been successful in algae control.
The common issue of controlling algae in both larger lakes and smaller ponds becomes more problematic in the summer months. Algae and aquatic plants provide oxygen and food for marine life, including fish. But excess algae in a pond can interfere with swimming and fishing. It can also cause unpleasant odors and other aesthetic problems such as mats of algae on the water’s surface.
Types of Straw Available
Barley is a type of straw used to control algae. But others, such as wheat, linseed, and lavender stalks, can be used as alternatives if barley straw is not available. But they will not be as effective in eliminating algae, nor will they function the same. If you decide to use one of the alternatives to barley, you must increase the application frequency and quantity used. Never use hay to eliminate algae, as it will release nutrients that will encourage its growth.
Barley straw is an acceptable alternative to using copper compounds that have toxic effects on rooted aquatic plants, insect larvae, fish, and zooplankton. It is a cost-effective and environmentally friendly way to control algae in ponds.
How Does It Work?
It needs to be used in a specific way to work. When barley straw is placed in water, it breaks down, and a chemical is released that inhibits algae growth. The breaking down of the barley straw is a microbial process that depends heavily on the surrounding environment’s temperature. The chemical release occurs more rapidly in the summer and slower in the winter.
Initially, the algae may not appear to be affected by the barley straw’s presence, but after several weeks, it will diminish.
While it has been discovered that barley straw prevents algae’s growth, it does not kill algae already present in the pond. Thus, it is an algistat (an agent or substance that inhibits algae’s growth) rather than an algicide (a substance that destroys algae).
It has not been determined how barley straw prevents the growth of algae. It is thought to result from the straw decaying in the water that releases chemicals that inhibit algae growth. Another theory is that the decaying straw feeds certain microbes, which are algae, predators.
Conditions Required for Barley Straw to Work
Adding the barley straw to a pond does nothing until the decomposition occurs. This is called “conditioning,” which depends on several factors such as temperature, being the most important. Once properly conditioned, it will continue to work for many months. Barley straw extract may work faster as it is already conditioned.
The barley straw needs water and oxygen to decay. The straw can be floated on top of the water or just under the surface. The straw can also be placed in waterfall boxes, wetland filters, or under a waterfall. Pond aeration and moving water increase barley’s effectiveness.
How Effective is Barley Straw?
There is positive research-based evidence that barley straw effectively controls some kinds of algae. But which types are controlled? Evidence has shown that barley straw is effective in controlling planktic algae. It clarifies water that is green from algae. Research continues regarding its effectiveness in blue-green algae, filamentous algae, and mat-forming algae. Some testing results are positive for these types of algae.
Where Can You Purchase Barley Straw?
Barley straw is available in full-size square bales from feed stores or farm supply stores. This is an economical way to purchase it, especially when needing larger quantities to treat bigger ponds. Its availability in farm stores may be seasonal, depending on the location. Whole bales can be ordered from retailers online, but the cost is typically more than from a local farm store or feed store. Consult with government or private agencies that work with local farmers, such as Conservation District offices, extension offices, or farm supply companies, to determine if barley straw is available in your area.
You can also purchase various barley straw products for use in smaller ponds, including liquid extracts, miniature bales, and pellets. When purchased in smaller quantities, the barley straw’s cost is typically more per pound than if purchased in full bales. These smaller quantities are appropriate for smaller ponds such as water gardens and koi ponds. These products are available from pond supply stores, garden centers, and online retailers. These are the barley straw bales that we use.
Algae is the pond owner’s biggest problem. People try everything to get rid of it. Farm supply stores or feed supply companies sell barley straw bags in small amounts for the backyard pond.
Barley straw extract can also be used—pond barley’s benefits without the mess. It is sold as “straw in liquid form.”
Barley Straw – It is a Pesticide?
Barley straw is not considered a pesticide by the United States Environmental Protection Agency, so you don’t need a license or permit of any sort to apply it. It is regarded as a home remedy for the private landowner, but only on their private property. Any public property application should be approved by the governing body.
When Should Barley Straw Be Applied?
Because barley doesn’t kill algae, it is best to apply it in early spring, before the algae begin to grow. When applied to cold water, less than 50 degrees, it may take six to eight weeks for the straw to decompose and produce the chemicals that inhibit algae’s growth.
The decomposition process is temperature-dependent and is faster in warmer water. When the straw is applied to water above 70 degrees, it may become effective in as little as one or two weeks. Barley straw will remain effective for approximately three to six months after the application.
Where Should the Barley Straw Be Applied?
Spreading the barley straw in smaller quantities around the pond will improve the distribution of the growth-inhibiting chemical found in the barley straw bale. Place each net of straw equal distances from the shore and other nets. The placement of bags does not need to be exact. In larger bodies of water, practical considerations such as allowances for angling and boating may determine the bags’ placement. In small ponds, where only one net is needed, place it in the pond’s center or in an area where it gets water flow like a wetland, waterfall, or stream.
Barley Straw – How Much Should Be Applied?
The most common application is roughly two or three bales per acre of pond. The pond’s water depth is not a factor unless the pond is adequately aerated, which would circulate the pond water, increasing the barley application levels. In a pond that is muddy or has been known to have heavy algae growth, two or three times the recommended dose may be required for the first treatment. Ensure not to overdose the pond with barley straw as it deoxygenates the water as it decays and may kill the fish. This is especially true if overdosed during a warm spell, but you would need to add quite a bit of barley for this to occur.
Muddy pond water will require more barley straw than a clear pond. Some people have questioned whether the barley straw itself could become a problem with the microorganisms colonizing and absorbing the water’s oxygen. But the decomposition of the straw occurs slowly, and the use of oxygen by the microorganisms isn’t a problem unless large amounts of straw are used that are more than most pond owners will ever need. If you have a muddy pond, it is highly recommended that it be heavily aerated and treated with bacterial tabs to reduce the sediment levels.
The amount of straw required to control algae’s growth depends on the surface area of the pond. Ponds that historically have problems with algae need treatment at a ratio of 225 pounds of straw per surface acre. This rate is about 0.8 ounces of straw per ten square feet of pond surface area. You can try lower doses, but do not fall below 90 pounds of straw per acre or 0.3 ounces per ten square feet.
The straw is less effective if it is in muddy water, so a higher dose is recommended in bodies of water that are incredibly muddy or have very severe algae problems. In this case, apply 450 pounds per acre but do not exceed 900 pounds per acre. The straw requires oxygen to decompose, so using amounts greater than 900 pounds per acre could significantly reduce the oxygen content that could kill or stress fish.
As the algae begin to subside, the amount of barley straw can be reduced.
Calculating the Amount of Straw Required
The following example will determine the amount of straw required to treat a pond of five acres that does not have an excessive amount of algae or is not too muddy.
The pond’s surface area is five acres; therefore, the selected dose is 225 pounds of straw per acre.
So, multiply acres by pounds. For example – 5 acres x 225 lbs./acre = 1125 lbs.
To calculate the number of bales required, divide the total amount of straw needed to treat the entire pond by the single bale weight. The bales vary in weight, but 45 pounds is probably average. For example – let’s say that one bale weighs 45 pounds – 1125 lbs ÷ 45 lbs. = 25 bales.
How is the Straw Applied?
Large Pond Application:
It is essential that the bales are appropriately placed in the pond for maximum effect.
The strawbales must be broken apart first. If the bales are too tightly packed, it will not allow for adequate water movement through the straw since many large ponds lack proper water movement or aeration.
The loose straw should be placed in some type of netting. For larger ponds, wrap the straw in the cylindrical netting used for wrapping Christmas trees. This type of netting can be used for straw-filled tubes up to 65 feet long and can contain about 110 pounds of straw.
For smaller ponds requiring less straw, use loose woven sacks, such as onion sacks or nylon stockings.
Suspend the straw-filled netting with floats in the first three to four feet of the pond. If it sinks below this depth, the straw will not be as effective. The water movement near the surface will keep the straw properly oxygenated while distributing the growth-inhibiting chemical throughout the pond’s upper portion.
It is recommended that the floats be inserted inside the netting when the netting is filled with straw. The netting is then anchored in place using a rope attached to concrete blocks or bricks.
Small Pond Application
For small, lined backyard water garden ponds, it is generally recommended that approximately 16 oz of barley straw will effectively treat up to 5000 gallons for up to three months.
Barley for small ponds is often sold in mesh bags or fully biodegradable bags. The biodegradable bags are typically preferred as the entire bag and barley straw can be left to fully decay in the pond and will not require cleanup or removal.
The straw needs water flow to decompose properly, so place the barley bags in the pond’s waterfall box, wetland filter, or stream to ensure maximum water flow through the barley straw. In ponds lacking any of the above features, place the barley near the circulating pump or the aerator to provide the necessary water movement and oxygen for proper decay.
Other Ways to Control Algae in Ponds and Lakes
Excess algae growth is promoted by an increase of nutrients in the water, particularly phosphorus. All runoff water of any sort will carry nutrients, especially from pastures, farms, fertilized lawns, roads, malfunctioning septic systems, or wildlife excrement.
To reduce the algae growth in a pond, you need to increase oxygen and decrease nutrients.
Use surface aeration to disperse the algae and to minimize the effects of die-offs.
Remove filamentous algae with rakes or nets.
Use bottom aeration for increased water oxygenation and reduction in long-term sediment build-up, which will reduce nutrients.
Divert nutrient-filled runoff from entering the body of water.
Prevent large groupings of geese and other wildlife from frequenting the body of water. A few is fine; a bunch is a problem.
Treat runoff with buffer strips of grass or vegetation before it can enter the pond or lake.
Reduce phosphorus fertilizer use from nearby lawn areas.
Apply bacteria and enzyme tablets to help break down debris and reduce overall nutrient levels.
Every pond owner deals with algae at some point. While there are many products available, the best alternative to controlling algae naturally is organic barley straw. Help save the earth naturally by not using chemicals. Organic barley straw is by far the best option!
As an Amazon Associate I earn from qualifying purchases.
