Closing the loop on sustainability
By Christopher Pollon
Beginning next May, visitors to Michelle and Jim Lester’s Newfoundland farm will be able to buy fish and produce grown together in an “aquaponic” closed-loop system that reuses waste and water.
“Aquaponics is basically a recycling system that replicates nature,” says Michelle of the 11,000-square-foot system now being built on the couple’s agro-tourism farm located just inside St. John’s city limits. The fish provide nutrients for the plants, the plants take up the nutrients, and by doing so, the water is cleansed of ammonia and nitrate, allowing for the nutrient- and beneficial bacteria- rich water to be perpetually looped. “It is the most environ- mentally friendly way of growing food.”
Michelle was inspired to take up aquaponics after discovering the farming practice on the Internet – and reading about farms in the Middle East and Australia where the practice is already established. Not only were the Lesters able to attract support from three levels of government to create a pilot project at their farm, they tapped the expertise of Memorial University-affiliated experts in St. John’s (see sidebar). While carp, catfish and barramundi can adapt well to aquaponic systems, the choice was made to raise tilapia (a warm freshwater fish native to Africa) because the species grows quickly and is naturally disease-resistant. In the first year alone, the Lesters expect to produce about 6,800 kg (15,000 pounds) of tilapia – visitors to the farm.
It’s fitting that the facility, which will be sold directly to which will be just the second commercial aquaponics operation in Canada by next May, will be in Newfoundland – an island lovingly known by locals as “the rock” due to its predominantly stony, unarable land. The aquaponic produce will not require soil at all. Instead, the plants will suck nutrients from recirculated fish water that would other- wise be disposed.
“Replicating a completely natural biological system means I can sell these products to my customers and give them 110 per cent assurance that it is a pure product,” says Michelle.
What is Aquaponics?
A relatively new field of agriculture, aquaponics is set for huge growth worldwide according to Wasiim Kader Bathia, a Memorial University MSc grad and aquaponics expert who has overseen the design and engineering of the Lester’s system. The benefits are obvious, he says. Traditional aquaculture requires the discard of 10 per cent of polluted water a day, while aquaponics discards zero waste, losing less than 1.5 per cent per day (mostly from evaporation). Aquaponics can be established virtually anywhere, and compared to field production or hydroponics, the yield is much higher, in part because the perfect nutrients are always in contact with the roots.