SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/fish-outage-save-filter-bacteria

In a long power outage, how can you keep your filter's helpful bacteria alive?

Move the filter media into aerated tank water.

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  1. Put the media in an aerated tank or container ✔
  2. Rinse the media under hot tap water
  3. Leave it sitting in the stopped filter

Why: The bacteria that break down ammonia need oxygen to stay alive. A UF fish vet says to take the media out of a hang-on-back or canister filter and place it in an aerated tank or container, then put it back when power returns.

Huh, didn't know that: For loose canister media, Florida Sea Grant suggests a mesh bag hung in the tank.

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Answer: Put the media in an aerated tank or container. The bacteria that break down ammonia need oxygen to stay alive. A UF fish vet says to take the media out of a hang-on-back or canister filter and place it in an aerated tank or container, then put it back when power returns.

  1. Florida Sea Grant: Q&A, How to Keep Your Fish Tank Safe During a Power Outage www.flseagrant.org/qa-how-to-keep-your-fish-tank-safe-during-a-power-outage
    place it directly in an aerated tank or container to ensure the beneficial bacteria stay alive.
    Checked 2026-10-11.

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