I have had my aerator going all winter at 7' depth. I see quite a few dead BG and a lot of BG &LMB w/ fungus spots. I think next winter I'm going to pull into maybe 3-4' of water to keep deeper water from cooling to much. I just hope the fungus disappears cause I've got some nice 10+" BG now. I shut it off yesterday since weather is warming up. I don't know if that was right thing to do.