This is an interesting documentary. A bit biased, but does present both sides.

Weds. April 21, on PBS/KCTS channel 9:
Net Loss: The Storm Over Salmon Farming

In the Pacific Northwest, salmon are at the heart of people's diet and culture, but decades of poor fisheries management and habitat loss are threatening wild salmon runs. The international salmon farming industry produces huge quantities of relatively inexpensive fish raised in ocean netpens, but in the process may be threatening the fragile marine environment, the economies of local coastal fishing communities, and possibly human health. Scientists, industry spokespersons, traditional fishermen in Chile, indigenous people in Canada, and others provide both global and local perspectives on this industrial approach to producing salmon.