I have had 2 d'oh moments with my little hundred gallon stock pond. Last summer the pond was evaporating fast so I would turn the hose on to fill it and walk away to do other things. Hours later I would remember and its was to late. The pond had 100% brand new tap water and I killed my koi and goldfish. Did that twice, since then i stand there untill im done filling.

More recently with my ICECAP 660 Ballast. I could not figure out what was going on with it. It was wired correctly and would not come on and stay on. I replaced the fuse and still nothing. I mailed to the ICECAP headquarters for repair ,and get a call that the fuse was not seated correctly and that was the problem. So I waisted money on shipping to fix something that was not even broken. d'oh