Thanks. I've found that the for winter aeration, coarser bubbles are better because of the wave action they make. OR shove a LOT of air thru the fine bubble membrane diffusers.

I have a single membrane diffuser that will open up an area 30-50 feet in diameter depending on the ambient temp. and ice thickness. BUT I'm shoving more air thru it than recommended by the mfg.
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).