I find this response rather comical as I peak at the grocery cart full of farmed onions, bananas, nuts, potatoes, black beans, chicken, duck, pork, radishes, frozen broccoli, bread... I mean I could really go on and on. If you look at what you purchase on a day in and day out basis you eat nothing but farmed food. And a lot of it is produced on a mass scale started back during the Green Revolution.
Farming has been around for, to be in specific, a long time. Farmed fish, on a massive feed the world scale, has been around for around 70 years. It is new and in the infancy of its scientific study. Some farmed fish are better than others for many different reasons. If you read Paul Greenberg's book you will hear a lot about the history of modern aquaculture. And in is book he talks about ow farmed salmon, even poorly done, as less negative impact on our world than pig, chicken, and beef farms. There is still a long way to go in working through the ecology of farmed fish but it is the future of fish mongers.
Who will help to discern the difference between farmed fish for the general shopper. Talked to your monger. He knows a lot.
The topic of farmed fish will be a never ending one for the Fishmongers Preservation Group.