Land-based fish rearing is significantly better option from a variety of perspectives. Certainly the effects of tides and storms are reduced, waste can be collected and treated, etc.

The big BUT is water. Cowlitz Salmon uses, I believe, 100 cfs to rear their production of smolts. Where will you find a couple 100 cfs of clean water and then be willing to keep fish that might carry pathogens out of the water supply? I have been told that there are filtering technologies that could clean up the water but that would add so much to the cost. But, the discussion needs to occur.