Jpsdad - The 12' dual has the pipe. So far it has been the first hole to reopen every single time. The pipe is not over the plume and no air from the diffuser actually goes through the pipe. The pipe is sunk in the mud and the diffuser is right up against the pipe as close as I can get it. All the pipe is doing is prevent the dome from fully forming. I THINK the sun on the pipe is melting just enough of a gap for the air to escape and the ice cannot rise.

Keep This Forum Viable, Read Pond Boss Magazine -
America's Journal of Pond Management