Water Change With External Filter?

[Dutsey]

Daft question but when doing a water change should I switch my external filter off

 

[Noahs ark6]

Daft question but when doing a water change should I switch my external filter off

If the inlet pipe (the pipe that water goes into the filter throguh) will be out of the water then you'll need to turn it off. If the pipe will be in the water at all times, you can leave it on

 

[OldMan47]

It is always safer to shut off the filter and heater before a large water change. Either one run dry will fail rather quickly. Once you are done, don't forget to restart things.