Hi. I've been lurking this site for ages, but haven't had an unanswered question until this one--thanks all!! We have a 3/4-ac clay pond, 12' deepest probably 6' avg. I have an airstone in the middle and a fairly large waterfall on a corner with a 12kgph pump. I've read some about wintertime bottom aeration posing a risk of driving the temperature throughout the water column down to a dangerous level. Am I on solid ground thinking that the best winter strategy in this situation is to turn off the airstone and let the waterfall keep the ice open in the corner (thus, in a good winter, leaving most of the pond safe for people and dogs)?

Glad to finally join, and thanks in advance for your thoughts.

I have never tested the affects of the thermal plume from a waterfalls. Variables will be depth of the water intake and the extent of the "reach" from underwater currents moving away from the falls.

My first thought was ice damage to the rocks in the falls. If water gets in between and freezes, you may have some water loss or rock movement.
Robert B