As reported by the CBC, a company in south central Ontario has developed a closed loop system in which fish fertilize cannabis plants, while the cannabis plants filter the water for the fish.

Green Relief facility in Flamborough, Ontario is the only licensed cannabis producer in the world growing using aquaponics — an advanced, soil-less form of sustainable agriculture where fish and plants are grown together in a natural ecosystem environment.

Aquaponics combines the best attributes of aquaculture and hydroponics, without the need to discard water or add chemical fertilizers. It produces 10 times the crop yield per acre and uses 90% less water than conventional farming.

“This is the agriculture of the future,” stated Warren Bravo in an interview with the CBC. He is a former concrete contractor who co-founded the company with friend Steve LeBlanc in 2013. “If you’re not latching on to sustainable agriculture technologies now, you’re going to be a dinosaur.”

Green Relief’s closed-loop system, which raises 6,000 tilapia and 4,500 plants at any given time, uses 90 percent less water than conventional agriculture, while delivering 10-20 percent better yields than traditional methods, Bravo said.

Every five weeks, Green Relief purges one of its 16 fish tanks, donating some 300 market-size tilapia to Second Harvest, a food charity which delivers the fish to a homeless shelter’s kitchen.

A $60 million expansion is underway at the company’s rural base outside Hamilton, about an hour’s drive west of Toronto, which will add 15,000-20,000 kilograms to annual output. The project also includes manufacturing and packaging operations, to process plants from its satellite operations.

With partners, Green Relief is also building facilities in Thunder Bay, Ontario and Halifax, Nova Scotia that will each produce some 20,000 kilograms annually, Bravo said.