trialsguy, you are on target for your location, 45-50F water once saturated will hold 11-12 ppm DO, I prefer a winter option of being able to open the ice (only with snow cover)in a very shallow area.Clear ice (even 2 ft thick)will still allow enough light for a 02 production.Maintaining open water all winter in a small pond will have more negative factors than positive.In larger bodies especially with a history of DO problems small areas of open water are OK as warm pockets of deeper water will always exist.Last year in NW Ohio we had ice on/off six times throughout the winter and we never recorded any less that 90% DO saturation in any of the ponds we manage.We actually lost some November stocked redear due to Dec temps that got into single digits with high winds that super cooled small ponds that had no ice formation yet, So ice can be a great winter blanket to help keep that 39 F bottom water from getting any colder.Also keep in mind that when the night temps dip below the water temp that the surface water is getting pushed down and a natural mixing is taking place If you are aerating 24/7 now with the approach of winter cut back to night only and stop when suface is 40-50 and falling. I have shut mine down as is 34F this AM with 22 mph west winds and that is actually too much circulation but mother natures rules this time of year.I see more small ponds in the midwest being over circulated than under aerated as a little DO goes a long way in the winter.
