Tom you are probably a little brilliant and a litte psychic!. I went to check my co2 and it had emptied!!!!! It had maybe a few bubble left, but must have been running on low pressure for a couple of weeks because when I upped the bubble count, my cannister was empty within 2 hours.

I never thought of that because it had been filled 3 months ago and the last cannister lasted 8 months -- I figured this one for a year because I had taken your advice and had started shutting it down with the lights.

No wonder I've been fighting algae!!! eesh. the only co2 hit those plants were getting was during weekly water changes. I wasn't even using excel.

Canister gets filled first thing Monday morning when the place opens!! Thank you.