The most simple definition of Aquaponics is the combination of aquaculture (raising fish) and hydroponics (the soil-less growing of plants) that grows fish and plants together in one integrated system. The fish waste provides an organic food source for the plants, and the plants naturally filter the water for the fish.
The third participants are microbes (nitrifying bacteria). These bacteria convert ammonia from the fish waste first into nitrites, and then into nitrates. Nitrates are the form of nitrogen that plants can uptake and use to grow. Solid fish waste is turned into vermicompost that also acts as food for the plants.
In combining both hydroponic and aquaculture systems, aquaponics capitalizes on their benefits and eliminates the drawbacks of each.
Extremely popular in China, this horticultural method has a long history due to its efficiency in growing plants.
The plants that are best adapted to aquaponics include, but are not limited to, watercress, herbs, chives, basil, Chinese cabbage, and spinach. Some horticulturists can also grow lettuce using the aquaponics method, but this is not a widespread technique. Vegetables and fruits with a higher density and nutrient requirements such as cucumbers, tomatoes, and peppers require a far higher fish density.
Fish excrement is an excellent fertilizer for the plants. Many fish farmers choose to raise freshwater fish, along with prawns and crayfish. Tilapia is a very popular choice because this particular fish is practically immune to the rapidly changing water conditions. They are also tolerant of the crowding that occurs in aquaponics tanks. Other types of fish found in aquaponics include the Pangus, Koi, Magur etc.