Are you saying as a rule of thumb the bottom of the pond will be at, or around, 39°F through cold months, or with aeration it should be at 39°F through cold months? It was my understanding that the bottom of my pond would hoover around 50-55°F year round (without any type of aeration/siphon pulling cold water off the bottom)?
My system is rated at max. efficiency with the following incoming water temps:
50°F/heating
59°F/cooling
Given the fact that my pond is mostly spring fed, there would not be enough "flow thru" to change bottom temps that drastically with a bottom siphon type spillway. However, I like the idea of removing water from the bottom as opposed to letting it flow off the top (current state).
