Very interesting. I have always wondered why it wasn't done more like this but maybe it's just not been effective or the tech needed a lot more work still. Archive: https://archive.today/tYoaT From the post: >>Giant containers which will separate wild and farmed fish could revolutionise the high-demand industry. A new fish farm on Loch Long will use the pollution-limiting containers next year if planning is approved. Environment agency Sepa has granted a licence for the semi-enclosed vessels in a move welcomed by conservationists. It is hoped other sites will follow suit.