I have never had doming of the ice above the diffuser. Maybe this is because I don't start my aerator until the ice is 5"-6" or more thick. Ice that thick will have a great amount of weight and it is not likely to lift off the ice. The bubbling then just "eats" a hole in the ice.

Last edited by Bill Cody; 01/21/20 05:51 PM.

aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
America's Journal of Pond Management