Originally Posted by Knobber
I will report back on the temps, before and after.

I'd suggest that photoperiod has a much bigger influence on water temps this time of year compared to aeration.
We're losing several minutes of light every day. Less light on the water = less energy added to the water = cooler water.

During the hot part of the year I run the air pump from midnight to 7:00am. When September gets here I start shifting
the run time to daylight hours. I'm running 2:00am-9:00am now. I'll move it an hour per week until it's only running
during daylight hours, then move the diffuser up shallow around the end of October and run it 24/7 all winter.

Anecdotally, two weeks ago surface temps here were in the mid 80°s. This morning the surface temp is 73.8°.
It was more comfortable for human swimmers two weeks ago. I expect the fish are liking it more now.


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