Growing both fish and crops in one system is not what most imagine when thinking Agriculture. I have found it to be a fascinating system. Since January I have been partaking in a college Aquaponics course. It can be a strange idea, growing plants using fish waste as a nutrient media. However, if properly managed there is scant chance that harvested crops will have any sort of contamination, even e-coli. That is resultant from the waste only of warm blooded mammals. One of the largest advantages of this method of growing plants is the amount of water used. At its most efficient Aquaponics systems can operate while using up to 90% less water than traditional agricultural methods. This is a result of the water being nearly all covered or only come into contact with plants. As a result the loss of water is limited almost exclusively to surface evaporation. Since the exposed surface area is limited so to is the evaporation.
How does Aquaponics work?
Fish or certain shellfish live and are raised in tanks, and the waste they produce are then transported to plants which feed from and filter the water that is returned to the fish. Thus aside from the initial filling with water, and electricity, feed for the fish is the largest operating cost.