We have a 3000 litre fish tank (see above) that contains a submersible pump. Water is pumped up to the two grow beds above that are filled with gravel and vegetables. The water contains all the fish waste (ammonia, nitrates etc) and when it is pumped to the grow beds, it fertilises the plants organically. The water then falls back into the fish tank as clean water.
In aquaponics, the nutrient-rich waste-water from recirculating aquaculture provides a food source for the growing plants and the plants provide a natural filter for the water the fish live in. This creates an ecosystem where both plants and fish can thrive. Aquaponics is the ideal answer to a fish farmer’s problem of disposing of nutrient rich water and a hydroponic grower's need for nutrient rich water.
The key to a successful aquaponic system is a healthy colony of beneficial bacteria. These bacteria convert fish waste into nitrate and other elements which are used by plants as they grow. Without the bacteria, ammonia and nitrite levels, which are toxic to fish and plants, would quickly rise.
Aquaponics can be used to produce large quantities of food in very small spaces in an environmentally friendly way.
We have enough room to humanely farm about 100 silver perch, a fish that is native to Australia's Murray-Darling river system. We chose silver perch as they're a good beginner fish, they taste good and can tolerate a wide variation in temperature.
If you're thinking of setting up a system, you'll get all the help you need here: