Explore this delicious eco-friendly fish.
The system (which can be used to grow nearly any fish) is particularly efficient when you’re raising tilapia, omnivorous fish that can get all the nutrients they need from small plants, algae and bacteria. Carnivorous fish, such as salmon and tuna, on the other hand, need to eat smaller fish. “Farming carnivorous fish has a fairly significant environmental impact,” says Duffy. “Scouring the ocean for the prey fish can harm ecosystems.”
Tilapia don’t just survive on simple plants and microorganisms, they thrive on them: tilapia utilize nutrients more efficiently than other fish, thanks to a digestive tract that, extended, is about 13 times their body length. (A trout’s is less than three-quarters the length of its body.) “That gives them a lot of time to extract nutrients,” says Timmons. And because tilapia are so good at converting plant fuel into high-quality protein, they’re an economically wise choice. “Tilapia is by far the most sustainable commercially available fish,” says Timmons.
So what’s the catch? Not all tilapia farmed worldwide are cultured in recirculating systems. So try to buy tilapia grown stateside. Likely, its source won’t be identified. Ask at the fish counter.