Someone with a couple of fish cages should do a winter test to see fed vs not fed growth rates thru winter.
Just a TX observation, but using a shallower cage increases the amount of food a caged CNBG will eat. In cold water, CNBG usually retreat to the lowest part of a cage, and are not inclined to rise into the colder surface water. Those that are in that same water temp as the surface (shallow cage), seem to eat much better.
Just throwing this out there for anybody that want to try a winter cage test.
