Hydroponic Urban Agriculture which can be run on fish waste water from intensive fish farming. This is called aquaponics. The plants clean the water for the fish, the fish water nourishes the plants as it is pumped around the system.
This guy is on the cutting edge of urban agriculture. Troughs of bok choy stack up vertically at the urban farm in Singapore. The veggies rotate along the A-frame to ensure they receive even light. Click through to read the full article.
INFOGRAPHIC: How vertical farming could help cities feed themselves