What else could be more beneficial than growing vegetable/food crops using the water existing in your own backyard? This smart technique is known as Pond Water Aquaponics. You do not need to fertilize your crops or water them periodically because they will receive the nutrients and water from the pond. The most important output of small-scale aquaponics production is vegetables.
Over the past 30 years, the use of pesticides and synthetic chemicals has increased so much that it seems the growers have started thinking it’s impossible to grow something or anything without applying chemicals. This makes it hard for folks to even purchase vegetables without wondering whether they are poisoning themselves in the process. Luckily for us, it is possible to grow our very own vegetables in our yard by using our pond or water garden.
Table of Contents
The System Required For Pond Water Aquaponics:
People having backyard ponds are rarely aware of the concept of growing veggies using that pond water. Ponds are the ideal source of nutrients, especially if they contain freshwater fish.
To have a successful pond aquaponics system, you need two parts:
- Aquaculture for aquatic animals – if you have a pond with any animals, you already have this part. This is where we will get the needed water and fertilizer for the plant.
- Hydroponics for growing plants – This is the part where we need to get creative and find a way to grow food sources in the water from our pond.
Typical Components of an Aquaponics System:
- Rearing tank – This is traditionally where the fish are raised. For us, it is the pond.
- Settling basin – This area is used to collect the uneaten fish food and remove biofilms and any other kind of sand, rock, or waste in the water. For us, the pond bottom or perhaps an intake basin will do.
- Biofilter – A system that uses living elements like nitrifying bacteria to decompose the pollutants and nutrients and convert them into food for the plants. This might be a wetland filter, floating island, or any sort of strata that will encourage bacteria colonization.
- Sump – The last and the lowest part of the system collects the additional water to recirculate it back to the tank or pond.
Typical Components of a Hydroponic System:
- Media bed using cotton wool – Often used by home gardeners. It contains a rectangular tray with compartments and holes at the bottom. The spaces are covered with wet cotton wool to conserve moisture. These are often used to start seeds inside the home or a greenhouse before it is warm enough outside to plant. Although the root areas will overgrow the containers, they can also be used as long-term planting structures for this system.
- Nutrient film technique – This consists of a net cup filled with gravel or any other growing media, an extender, and a grow tube. The system works well for ponds and streams because it is easily installed, provides proper air and water circulation, and produces healthy plants.
- Deep water culture – Utilizes no medium, just a mesh cup or pot with gravel to support the seedling. This can be used individually or within a tray system for multiple plants.
The Potential of a Constructed Wetland Filtration System:
Constructed wetland filtration systems are typically installed in or near bodies of water to utilize marginal aquatic plants to filter and clean the water. Water is pumped from the body of water, and either pushed up through the filter from the bottom or simply ran over the system’s top. We can utilize the wetland filter model to grow our vegetables rather than merely cleaning water using pond plants.
- The pond water cleaning plants are now your vegetables
- You might want to continue to use aquatic plants and simply add your vegetables to areas not already crowded with aquatic plants
- You may need to clear aquatic plants and their roots out of the areas where you would like to grow your vegetables
- Wetland filters are typically already in full sunlight areas, so they are great for vegetables
- The vegetables never need water and get their fertilizer from the pond water.
- They work very well for leafy vegetables like Lettuce, Spinach, Cabbage, Kale, Coriander, etc.
- Wetlands are typically topped with small gravel just below the water level. For growing vegetables, you will likely need to add more gravel. The system is areas to create growing conditions suitable for your veggies. Aquatic plants typically like 1 “-10” of water over their roots, which is not the case with vegetables.
- For the best results, you will want to start with seedlings rather than sow seeds into the gravel.
The Potential to use the Pond Edge or Border
Not every pond will have a constructed wetland filter, and not every homeowner will want to spend the time and money to build a wetland filter, so the previous section may not apply to you. One thing that every pond owner has is a pond edge or border.
- You will want to start with seedlings rather than seeds.
- You will need to use some sort of container or gravel to hold the seedlings at the proper level at the edge of the pond.
- Different plants will tolerate different exposure to water, so this is something that you will need to experiment with.
Vegetables and Herbs that are Good to Grow In and Around Ponds:
- Lettuce, Tomatoes, Basil, Spinach, Okra, Coriander, Cucumber, Red Salad Onion, Peas, Cauliflower, Cabbage, Eggplant, Parsley, Sweet Potato, Kohlrabi, Reddish, Turnips, Melons, Capsicum, etc.
- Basil (Ocimum basilicum), Chamomile (Matricaria chamomilla), Hedgehog coneflower (Echinacea purpurea), Feverfew (Tanacetum parthenium), Johnny Jump-up (Viola tricolor), Parsley (Petroselinum crispum), etc.
Benefits of Pond Water Aquaponics:
- Sustainable integrated aquaculture and food production – The world population is increasing at the rate of 1.05% annually, and freshwater availability in every region of the world is decreasing day by day. Using the pond aquaponics technique, you are conserving water, and you can grow protein-rich fish and organic veggies simultaneously.
- Increased productivity and efficiency – You can produce everyday food in your place, saving trips to the market and using the existing water at your home to create edibles. The plants growing in your pond system are also helping to take nutrients out of the pond water, which will decrease the unsightly algae growth in the pond.
- Organic Food – The vegetables and fish in your pond are entirely under your control. You will be able to ensure that no chemicals or additives are in your water, so you will never need to question the quality of the food you produce. Be sure not to use chemicals anywhere in the watershed of the pond, and you are all set. Gowing your own organics will be very invigorating and will save you money. The prices of organic products are 100-600% higher than the inorganic ones. It could be a profitable business at the same time as you might be able to sell some of your edibles.
Water Conservation:
Pond aquaponics is a new technique in Olericulture in terms of the use of minimum water instead of flood irrigation. Water resource shrinkage is one of the major global issues. Pond aquaponics and wetland-associated food production are conserving the water and purifying the used water.
Aesthetic Value and Monetary Opportunities:
Almost one century back, there were no supermarkets where fresh fruits, vegetables, or ornamentals were available for sale. Everybody was dependent upon the food they used to grow on their land, the climate was the healthiest, and the pollution was minimum. Pond aquaponics provides the same opportunity with the least effort.
Additional Benefits of Constructed Wetlands:
“Plants will clean the water to be used for other plants” this is the formula behind growing food crops in the constructed wetland filtration system in your garden. There will be no need to add fertilizers to your plants as the water will supply all they need. Constructed wetlands are the absolute best water filters that we can have for our pond. Using them to grow some veggies is a no-brainer.
Control of Soil-Borne Diseases:
Growing your veggies in your aquatic environment will remove the need for any pesticides or insecticides as there will be no soil-borne diseases to disturb your crop.
Closed-loop, Low Maintenance System:
A well-thought-out and constructed pond aquaponics system can be the ultimate closed-loop, low-maintenance growth system that you can find. Over time, with a bit of upfront experimentation, you can develop a system that pretty much takes care of itself other than planting and harvesting.
Research-Based Evidence Regarding Pond Aquaponics:
- Experiment for Nitrogen Transformation in Aquaponics using the two plants: Tomato (Lycopersicon esculentum) and Pak-Choi (Brassica compestris subsp. Chinensis). The Nitrogen Utilization Efficiencies (NUE) of both plants were compared symmetrically. The tomato plant NUE was 41.3% (due to the higher root surface area), and that of Pak-Choi was 34.3%. The abundance of the Nitrifying Bacteria in Tomato-plant aquaponics was 4.2 folds higher than Pak-choi. The third parameter measured was water quality. The water quality of tomato-based AP was better. The contribution of the tomato-based aquaponics into the environment, in the form of N2O, was 1.5-1.9%, determining the potential anthropogenic (N2O emission into the atmospheric) ability of aquaponics. (Hu et al., 2015)
- A 54 days experiment was conducted at the “AIT, Thailand” to determine the impact of pond-water filtration effect on the following:
- Growth media: lettuce grown on sand media followed by gravel was found to have the highest yield and head weight compared with the control treatment.
- Yield of Lettuce: the partially filtered pond water supports an 87% higher yield compared with that of unfiltered water. (Sikawa & Yakupitiyage, 2010)
References:
Blidariu, F., & Grozea, A. (2011). Increasing the economical efficiency and sustainability of indoor fish farming by means of aquaponics-review. Scientific Papers Animal Science and Biotechnologies, 44(2), 1-8.
de Farias Lima, J., Duarte, S. S., Bastos, A. M., & Carvalho, T. (2019). Performance of an aquaponics system using constructed semi-dry wetland with lettuce (Lactuca sativa L.) on treating wastewater of culture of Amazon River shrimp (Macrobrachium amazonicum). Environmental science and pollution research, 26(13), 13476-13488.
Hu, Z., Lee, J. W., Chandran, K., Kim, S., Brotto, A. C., & Khanal, S. K. (2015). Effect of plant species on nitrogen recovery in aquaponics. Bioresource technology, 188, 92-98.
Palm, H. W., Knaus, U., Appelbaum, S., Goddek, S., Strauch, S. M., Vermeulen, T., . . . Kotzen, B. (2018). Towards commercial aquaponics: a review of systems, designs, scales, and nomenclature. Aquaculture International, 26(3), 813-842.
Pantanella, E. (2008). Pond aquaponics: new pathways to sustainable integrated aquaculture and agriculture. Aquaculture News, May.
Rakocy, J., Masser, M. P., & Losordo, T. (2016). Recirculating aquaculture tank production systems: aquaponics-integrating fish and plant culture.
Salam, M., Asadujjaman, M., & Rahman, M. (2013). Aquaponics for improving high-density fish pond water quality through raft and rack vegetable production. World Journal of Fish and Marine Sciences, 5(3), 251-256.
Sikawa, D. C., & Yakupitiyage, A. (2010). The hydroponic production of lettuce (Lactuca sativa L) by using hybrid catfish (Clarias macrocephalus× C. gariepinus) pond water: Potentials and constraints. Agricultural water management, 97(9), 1317-1325.
Somerville, C., Cohen, M., Pantanella, E., Stankus, A., & Lovatelli, A. (2014). Small-scale aquaponic food production: integrated fish and plant farming. FAO Fisheries and Aquaculture Technical Paper(589), I.
