Aquaponics is an integrated food production system that combines fish cultivation (aquaculture) with plant growing (hydroponics) in a recirculating water system. Fish produce waste that is converted by bacteria into nutrients that plants can absorb; the plants clean the water, which is returned to the fish. The system produces both fish protein and vegetables from a compact footprint with very low water consumption compared to conventional agriculture.

An aquaponics system can be integrated into a regenerative building as part of the greenhouse complex or as a standalone indoor unit. The water and temperature requirements of aquaponics (warm, clean, well-oxygenated water, and warm air temperature for most productive fish and plant species) align well with greenhouse conditions. A modest aquaponics system of 2 to 4 cubic meters of fish tank volume and a comparable area of growing media can produce 50 to 100 kilograms of fish and several hundred kilograms of vegetables per year from a space the size of a large living room.