Sustainable Symbiosis in Fish and Veggie Farming Germany’s first aquaponics farm. We’ve got a very low water usage and a very good CO2 record and because we are doing this in an urban environment, we don’t have long distance shipping or need for cooling during transport and have super-fresh products for our customers. In detail, sustainable agricultural production right in the middle of the city works like this: Rainwater is collected in tanks, and re-used for fish farming. A total of 13 tanks hold Tilapia, a.k.a. African Cichlid. Tilapia are highly efficient in terms of feed usage: 1.2 kilograms fish feed generate 1 kilogram of fish meat. That’s way better than in cattle farming. But the kicker in this system is that fish excrement is used as a fertilizer for the veggies next door. We’re using organic fish feed, the fish eat that, produce excrements both liquid and solid The solids are removed and go into the sewer system Liquid ammonia goes into a biofilter and is converted by microorganisms into nitrate and the nitrate is what we need for the plants. It goes underground into catchment tanks for the greenhouses and from there into the system. Next door in the main greenhouse, near tropical temperatures prevail. This is were eggplants, chilies and tomatoes grow. These veggies get almost 70 % of their organic nutrients from the fish farm. Nutrient-enriched water is first stored in tanks and later pumped to the plants. Here in this case we have drip irrigation, the plants sit in stone wool, each plant has its own nutrient supply line, I’m going to pull one out here: This is the drip irrigation. And the plants get watered in intervals that depend on how dry conditions are. And that’s all fully automated. To make this visionary way of farming work, some serious high-tech is needed. because aquaponics also means watching operations around the clock. A computer measures the water’s oxygen content, and data from a weather station is used to regulate the greenhouse’s climate. Some functions are accessible via cell phone apps. We’ve got different apps here, let me go in here and look at the aquaculture controller check for notifications and see what they are about, and reset things. I can decide if it’s important for me to intervene or not, and if it’s urgent, I can come here and take action. So, you’ve had emergencies? False alarms is what we’ve had but real emergencies, no. In the long run, the concept of this Berlin start-up is meant to be more than a trendy idea for hip city dwellers. The goal is to sell this type of system around the world. A grocery chain from Switzerland has voiced interest. Our business model on the one hand is to plan and build these large farming systems, and the farm here is our reference, which we are also using to show economic viability of the system. For that reason, we are selling everything we grow here directly to eco-conscious customers in the city. People who like organic, sustainable food. 30 tons of fish as well as 25 tons of herbs and veggies are what the city farmers are aiming for annually, right here in Berlin.