Okay, so I have gone through three heaters in the last year...different models and brands. The strange part, is these heaters are the only ones I have lost in 9 years since I started this hobby. And I really didnt know what I was doing except the last year or two. So here is my question, and forgive me if I am being ignorant, but does anyone actually unplug their heaters for water changes?? I never have, and I think technically you are supposed to, but in 8 years it was never a problem. Anyone have any thoughts??