It always seemed to me that the fish farms, which have been terrible marine polluters, could very profitably use the effluent to support secondary fisheries.
Perhaps shrimp or other crustaceans , mussels, sea cumbers, urchins, etc.
Stacked in layers it would deal with a lot of the effluent, produce products and the processing byproducts could fed back to the salmon.
AQB should be setting up deals with fish, crab, shellfish and shrimp processors.
A varied diet enhances flavor, positively uses undesirable waste, and prevents fish boredom.
I mean, do you want to eat a chronically bored salmon?