filters on/off during water changes

Mine goes off because the water level is lowered enough to cause concern during that brief period of time between the lowering of the water and the re-raising. Now, as for the heater...if it is submersible but wouldn't stay under the lowered water level, that has gotta go off for fear of something bad happening.

If you have the heater as part of your filtration unit, by all means, turn BOTH off.
 
Mine go off. My heaters and filters are on one power bar, and my lights are on another, I just flip the power bars off when I do my weekly maintenance.
My FO (fish only) tanks are lightly stocked, I find I don't stir up much of anything when I vacuum the gravel, and I usually don't touch the substrate of my planted tanks.

-Richer
 
55 gal powerhead-operated UGF - I unplug the powerheads and the heater while gravel vacc-ing. I leave the overhead light on though, cause it can be really hard to see in there. Probably not a good idea though, since I don't have this outlet on a GFI... actually that outlet's not even grounded.
 
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