So I have a few questions, and forgive my ignorance on the subject. Is the reason that a pond's temp increases with aeration related to the outside air temperature due to the location of the compressor? (i.e. If your compressor is outside in 90-degree air, it's sending 90-degree air into the water, which is what causes the water to heat up.) If yes, would the opposite also be true, if the compressor is in a climate-controlled room, which could potentially send cooler air into the water?
The water tends to heat up due the the added exposure to the sun and ambient air temps. This is because the water is constantly being turned over bringing cooler water up and allowing it to "soak up" the heat. Eventually, you heat up the entire column of water. Some heating occurs due to the hot compressor air, but I am betting its negligible compared to the power of the sun and air temps.
