I have a small (1/4 acre) spring-fed pond in southwest Virginia. I installed an aeration system [Airmax Model AM30] two years ago when I moved here. The pond had a bad algae (Chara) problem in the drought summer of '02 which I successfully treated with Cutrine Granular. I installed the aeration that fall in hopes of alleviating potential O2 problems, and so I could stock trout. The system has been running 24/7 ever since -- and seems to have worked: my trout stocked 11/02 and 3/03 (including browns and brooks) have survived through two Virginia summers.
Question: How frequently do aeration systems like this need maintenance? I noted in the catalog from the supplier that they carry both a Repair Kit and Replacement Filter for the aerator. Anyone have either experience or guidance on this type of Airmax system? Am I already on "borowed time," or can I get another year (or more) before heavy maintenance is called for? What about the air stones -- maintenance now or later? Many thanks for any assistance.