DUggan, My supplier of adult chanel catfish tells me the cats (don't know about others) can not digest the food when their body temps are lowered to a point. They fed longer than I would thing usually mid to late Nov., but stop after that. My advice is just to watch the fish as you are doing. If they continue to feed, go for it. For me though I'm not charging my clients to fill up the smaller amounts over the winter so I just shut them down. Turn the duration time way back and you still can get some beneftis over the winter if you see them feeding.
