esshup - DO concentration in the aerated ice free area should be uniform top to bottom and toward the high concentration of above 9-10 mg/L. For DO readings all across the pond, I would start at the furthest area away from the open hole. If DO reading near the bottom is very close to what it was in the ice free area, then IMO DO is uniform pretty much throughout the pond. Fish activity helps to somewhat distribute water currents. However if you want to be most accuruate, then check DO at some midway points. Lowest DO concentrations should be near or within 12" of the bottom.
