Pond Boss Forums GENERAL QUESTIONS Water chemistry Dissolved Oxygen under ice, longer days

From pics your fish are active. How deep was the picture taken? I think the fish in 39F water can survive on 2ppm DO. How much snow cover is on the ice and is top layer of ice clear or milky? Clear ice should allow enough light to the water with plankton below clear ice to make 2ppm DO per sunny day. Check the accuracy of the DO tester. Check your tester. The DO in some water that you know has good DO such as a sample from open surface water shaken in a jar for fresh from a stream. That DO should be at least 8 - 10 ppm or higher.