It does not matter that they make aqua culture pollution free or not. Industrial fish farming world wide is not just about Salmon. Right now world wide much of the commercial fishing fleets have converted over to fishing for forage fish to feed aqua culture and other industrial farming. Right now there are few if any regulations on this type of commercial fishing. Up to 70 % of the worlds forage fish are being targeted without limitations to feed commercial farming.

We will not have to worry about the saving the worlds top of the food chain fish such as wild salmon if we deplete the forage bio mass as we humans are doing now. Our top of the order fish will starve to death with large chunks of the their food chain depleted.

But hey we will have plenty of cheap shrimp, Cod and salmon from aqua culture to eat until the forage fish population fall to where it can't even feed pen raised sea food..