wood,
this is very common over diffuser head especially in shallow water here in new york state most of our customers run them and they usally ice up around the first of feb. if there is alot of wind sooner if trout are in the pond or lake we suggest shut down . Do not try and walk out and try to collapse the ice around the diffuser this ice is stratifed ice and is not safe for foot traffic. We have approx. 206 submersed aeration systems in operation and each one seems to put a different set of rules on the table. Please do not go out to open the ice unless you are tied off and have a couple of buddy's to help


Scott Trava
Catskill Pond
http://catskillpond.com
scott@catskillpond.com
Returning Catskill Waters To A Simpler Time
EST. 1923