[Chopin’s] approach involves creating a whole ecosystem around a fish farm, so the waste generated by the salmon gets taken up by other valuable seafood commodities, like shellfish and kelp….
[T]here are rafts made of black PVC piping, sticking out of the water like catwalks. They are home to cultivated seaweeds and mussels — species that thrive on fish waste.
“What we are doing is nothing more than recycling the nutrients,” Chopin explains. “Instead of looking at them as waste, we look at them as nutrients for the next species.”
One of the best things about the story is Charles’ nuanced approach—he’s thoughtful enough not to present Chopin’s work as the solution to all the environmental downsides of farmed fish. As Charles describes, Chopin’s “integrated multi-trophic aquaculture”
addresses the mostly localized problem of water pollution, but it doesn’t address other problems with aquaculture: the spread of fish parasites, the escape of caged salmon, or — worst of all — the need to harvest wild fish to feed the salmon. That’s a big problem for inland aquaculture as well.
The full story is worth checking out; find both audio and text versions here.