My power just went out and I have a backup generator but don't know which filter to plug in and run for now either my nexx 110 canister filter or my marineland penguin 400 these are both on my 55g tank please help
Run the canister, you don't want it sitting stagnant for too long.
You can always pull the media from the HOB and stick it in the tank. This is also a good opportunity to thoroughly clean the HOB.
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