Well, I had the DO and temps measured in 1 foot increments in my pond in 3 locations top to bottom. DO concentrations were similar in all 3 locations and ranged from about 2.6 ppm at the top to about 1.3 ppm at the bottom. It looks like it will winter kill for sure unless I install an aerator and plow snow. I may decide to install an aerator in a year or two - I need that much time to save up for an aerator and convince my wife. Like I said before no reason to be in a hurry. If nothing else it is a beautiful pond and attracts quite a few ducks and geese in the fall - we also like to hunt waterfowl. Thanks essup, I thought that the fish would move to areas with higher O2 levels but it makes sense that they don't. I have seen isolated bays off of larger lakes winter kill and wondered why the fish didn't move out - makes sense that they didn't know to do so.
