Lately I've been obsessed with only feeding free-range meats and kibbles to my dogs. I decided to do some research about farm-raised fish, since I didn't really know much about how it works. I had been trying to decide if farm-raised was better or worse than wild-caught. This publication is incredibly informative, please read!
http://www.ciwf.org/publications/reports/in_too_deep_2001.pdf