If DO levels drop at night and are lowest at sunrise, isn't aeration mostly needed/effective at night??
DO is most needed at the end of night early in the morning near sunrise. But replace the word aeration in your statement abover with "water movement from lower to upper regions of the pond" since that is actually what your aeration equipment is doing. Yes, your needs for more DO is in the pre-dawn hours. But is moving lower water upward (which is actually what your doing) accomplishing that goal?
I do not know. I'm asking. It just seems to me we may be equating the pump running as adding DO (it does at the surface but does it where the fish are residing?) but ignoring what the pump is actually doing which is moving lower water (could be lower or higher in DO depending on a number of factors such as how much high DO water was moved to the lower region at an earlier time) to the surface.
I know more than I understand and I don't know enough. Sounds like something Yogi Berra would say.
