Some environmentalists and marine researchers view open-ocean fish farming with a wary eye. They are concerned that because open-ocean farming is out of sight, it may slowly fall out of mind. Many of the species to be kept down on the aquafarm are top-of-the-food-chain meat eaters, which have the highest market value. But they also are voracious, requiring anywhere from three to 25 pounds of feed - read smaller fish or fish meal - for every pound of meat in the farmed species. Concerns also have been growing over the spread of parasites, such as sea lice, from farmed fish to wild schools that pass by, as well as over the results of genetic mixing between wild fish and their escaped farmed cousins.Hard to raise trout near most large urban areas, I would think, and there are already a large number of commercial catfish and crawfish operations...I suspect that there are lots of environmental problems with them, too.
Sustainable aquaculture is possible if the right species and techniques are used, says William Mott, outgoing president of SeaWeb, a nongovernmental organization that supports sustainable aquaculture. If the motive truly is to meet demand for food, he says, more can be done with fresh-water species grown in urban areas close to their markets, rather than developing large marine feedlots offshore.
Update: Looking for an "approved" fish list? here. Of course, the farm raised shrimp I'm putting on the barbie later are on the "bad" list. Dang.