IF I had to make a choice between aerating at 12 hr night vs. 12 hr during the day, I'd pick the night.

BUT, with the caveat that the aeration system should be sized 2x the size of the system that would be running 24 hrs a day.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).