ECF Farmsystems has set up a novel urban farming system in Berlin, on the premises of what used to be Europe’s largest malt house. While one area houses tanks full of tilapia, a 1,000 sqm greenhouse holds endless rows of basil plants – and both are sold at local stores. Unlike most aquaponics systems, this one boasts two water circulation systems, allowing each to be set at the optimal pH value and the plants to be fertilized without harming the fish. The fish circuit provides water, CO2 and nitrates to the plant circuit, and the plant circuit supplies oxygen in return. This allows for a 70 to 90 per cent reduction in water use and for the fish to be raised without antibiotics. The company is now installing turnkey systems elsewhere, such as in Brussels, the future home of Europe’s biggest aquaponics roof farm.