It seems like I remember seeing in the past a link to a product that was for keeping ponds cool. It was floating balls that covered the surface. Am I remembering wrong?
I haven't seen that but I know of one hatchery that floated the high density 4 X 8 foam boards on their small flow through holding ponds in the summer. Perhaps once could float them around the shoreline where the water is shallowest? If I did it I would run the yellow rope you get at the hardware store over the top of it in a couple of places with the ends staked on shore to keep the wind from pulling it up or moving it around.
Unfortunately the high density foam board is no longer cheap brand new. I have heard of people getting good deals on it at building surplus stores though.
I don't need any measures taken as 45 gpm of well water flowing into my 1/10th acre trout pond 24/7 in the summer with steep sides keeps temps pretty low in the hottest part of the summer. Once I put a pier in and was able to measure the temp of the water column I was amazed at how low it was. Upper 90's air temp and water temp was in the low 60's the top few inches. Down from there to the bottom was right around 60.
I'm thinking the top would have been warmer but colder below that if I didn't run the diffuser at night. However I believe running the diffuser part time was imperative to prevent an anoxic layer from developing near the bottom. OTOH I really don't know as to what effect the incoming well water has and could prevent that.
It would be interesting to experiment with different approaches without jeopardizing the fish as in no diffuser running but well water, or running the aerated well water straight to the bottom vs. spilling it out on the surface.
Unfortunately with about 500 lbs. of trout upon harvest in the fall after a two year period I can't take the chance at fish that are worth as much as they are.
