Thanks appreciate the information and advice. I will start that procedure tonight and slowly increase each day. I'm thinking of getting a timer and running it after midnight to keep the water temps down as you mentioned.

How long do you go with that routine though? Like until you hit 6 hours or do you work your way back up to 12-24 hours of aeration time?

Thankfully there were no dead fish today, so I'm hoping starting the process the correct way will mean they can survive at least another month until the water gets too warm and who knows after that.

There are some trout right under the culvert pipe where the stream comes in, stream temp is 65, pond temp is 78 so that makes sense they'd be there. I was debating putting a small aerator in beneath the pipe to get some air into that thermal refuge for them (gravel bottom about 2.5ft deep) but now I'm hesitant to add more air to the pond...

Any ideas on if adding a small aerator to that thermal trout refuge area would do more harm then good?