Aquaponics is a sustainable way of growing food in a greenhouse that combines fish farming and vegetable production. In a circular system, the fish produce ammonia, which is toxic and must be removed from the pool, with their feces and food scraps. Ammonia therefore goes with the water through an organic filter, in which there are bacteria that feed on it and convert it into nitrates, which are fertilizer for vegetables.

The plants consume the nitrates, and the water is purified by returning it to the fish pool in a circular system. In the process, water circulates all the time, and therefore such a greenhouse uses 95 percent less water than other systems