Sustainable food from the roof

Fruchthandel Magazine 17/22

Oxygen generation for aquaponics

Fresh basil is produced sustainably on the roof of Rewe's Green Farming store in Wiesbaden. Water and plant nutrients are provided by aquaculture. The aquaponic farm system, which is used to grow 800,000 basil plants and 20,000 cichlids per year, is operated by ECF Farmsystems. An oxygen generator from Inmatec, which produces pure oxygen from the ambient air, ensures the necessary oxygen saturation of the water used in aquaculture.

Sustainable food production, close to the consumer, energy-efficient and resource-saving, that is the goal of ECF Farmsystems. The farm system supplier plans and builds aquaponic systems for its customers. The systems combine aquaculture for rearing fish and hydroponics for cultivating plants into a sustainable system. One part of the Green Farming Market houses the aquaculture water tanks where the fish are raised. "An adequate oxygen saturation of the water, which is provided by a rainwater collection system, is important for successful breeding. This is achieved by adding pure oxygen to the pools of water. The oxygen promotes fish growth and prevents the development of diseases - without the addition of antibiotics," explains Horst Nowosad (sales) from Inmatec.

Urban farming and regional food thanks to self-production of oxygen

The required oxygen is produced on site by an Inmatec oxygen generator. The oxygen obtained from the ambient air with a purity of 90% is fed into the pool as required. "To do this, sensors in the water measure the oxygen saturation and thus control the amount of oxygen that is fed in via a network of pipes and corresponding vents," Nowosad describes the process. Finally, in the greenhouse, located on the roof of the building, the water from the aquaculture, fertilized by the fish, is used to grow basil using hydroponics. This water contains important nutrients such as nitrate and phosphate, which promote plant growth. In this way, large amounts of food can be produced in a resource-saving manner even on small areas. “The aquaponic process is therefore considered to be very climate and environmentally friendly. The basil plants grown on the glass roof farm and the fish reared in 13 tanks are brought to customers locally in the Wiesbaden market and on short transport routes to around 480 Rewe markets in the region,” says Horst Nowosad.

Published in Fruchthandel Magazine 17/22

Fotos: © ECF Farmsystems