Pond Boss Forums AERATION Should I aerate? my new aerator

The pond turns over when the water temp is much colder. Water gradually gets denser until it hits 39°F, then it starts to become less dense. Until you can take the bottom temp, you won't know when the turnover happens. Once the surface water cools down to less than the bottom water temp the pond won't turn over.

So, say bottom temps are 55°. The water on the surface floats on top of the bottom water until 55°, then it starts mixing. At 54°F it sinks beneath the 55°F water and "turnover" happens.

If the trout survived last summer without aeration, I'd leave the deeper aerator off until surface (say 1' to 2' depth) water temps drop below 70°F. Then you can use the start-up procedure for the deeper diffuser. I believe I killed my trout by running my deep diffuser at night when ambient temps dropped below 70°F. I beleive the warmer surface water mixed with the cooler, deeper water and the O2 levels dropped, killing the trout.