Can I Turn My Betta Tank Filter Off At Night?

Can I Turn My Betta Tank Filter Off At Night

I don’t know why, but many beginner fish keepers often ask me if they can turn off the betta tank filter at night. I can guess why you might want to turn off the filter at night, but you really shouldn’t. An aquarium filter should always run 24×7 except only the maintenance time of the tank.

You should not turn off the betta tank filter at night. The filter should run all the time 24×7, otherwise the beneficial bacterial colony can die. The only time you can turn off the filter is during tank maintenance.

Why running the aquarium filter is so important? Why turning it off for several hours can risk the lives of your fish? I’ll answer all of these questions in the rest of the article.

Why The Filter Should Run 24×7?

The aquarium filter should run all the time in order to maintain & grow the beneficial bacterial colony of the aquarium.

The beneficial bacterial colony is extremely important for an established aquarium. They are the tiny invisible army that keeps everything stable in the aquarium. If your beneficial bacterial colony gets wiped up for some reason, chances are most of your fish won’t be alive for a long time.

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Why The Beneficial Bacterial Colony Is So Important?

The beneficial bacterial colony deals with Ammonia in the aquarium and turns it into Nitrite. Later on, the colony also absorbs Nitrite and produces Nitrate. Ammonia & Nitrite is deadly for fish and a little amount of them can kill your whole collection. That’s why beneficial bacterial colony is crucial.

Why Fish Keepers Want To Turn Off Filter At Night?

There can be many reasons why fish keepers may want to turn off the filter at night. However, the most common reason I’ve heard is the noise of the filter.

Most filter makes gurgling noise which can be unbearable at night when you are ready to sleep. Many of us are very light sleepers and need absolute silence for a peaceful sleep. In such case, a noisy filter can really create a problem.

However, that doesn’t mean you have the flexibility to turn off the filter at night. The filter must run on. What you can do is take some steps in order to reduce the noise of the filter.

How To Reduce Noise Of A Filter?

  1. If you are using a HOB filter, make sure the water level of the tank is not too much lower than the outlet of the filter. If it is, just increase the water level so that it is just below the outlet. That way, you won’t hear any water falling sound.
  2. If the filter is still making gurgling noise, something might have stuck inside the motor. Or, the motor might be covered with sand particles which are creating the noise. In either case, remove the filter parts carefully and clean each of them thoroughly under running water. This should reduce the noise significantly.
  3. If the filter is still making noise, then it might have gotten too old to function quietly. In such a case, you’ll need to buy a new filter. Just make sure you are buying one that has great quality. Don’t look for anything cheap. Look for quality. A good filter will pay you off for years down the road.
  4. After you set up the filter, make sure to fill the chamber with the old filter media from the old filter. In this way, the new filter doesn’t have to grow a beneficial bacterial colony from zero. It will already get a head start.
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Will Your Betta Die If You Turn Off The Filter At Night?

Your betta might not die if you turn off the filter at night or for 6-7 hours. However, that doesn’t mean you should turn off the filter any time.

As I have already said, the main job of a filter is to maintain the beneficial bacterial colony. If the filter doesn’t run for 6-7 hours straight, then it poses a great risk for the beneficial bacterial colony. The colony might get wiped out.

The beneficial bacterial colony getting wiped out means nothing but disaster for the aquarium. The colony is what keeps everything stable. Without them, the tank needs to be cycled again, algae boom may occur, the water might get cloudy and fish can die due to lethal toxin.

The Only Time You Can Turn Off A Filter

There is only one time you can turn off the filter. That also for only 30 to 60 minutes max. The only time you can turn off the filter is while doing maintenance.

By maintenance, I am meaning the weekly water change, cleaning the tank glass, cleaning the substrate, etc. While you are doing these, keep the filter turned off. But make sure the maintenance doesn’t take more than an hour.

Final Words

I hope by now, you understand how important the function of filter is for a successful aquarium. More important than the filter is the beneficial bacterial colony itself.

In order to grow and maintain that colony, we need to keep our filter running all the time. Otherwise, we can risk the lives of our precious fish.

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Muntaseer Rahman

About Author

Hello, I’m Muntaseer Rahman, the owner of I’m passionate about aquarium pets like shrimps, snails, crabs, and crayfish. I’ve created this website to share my expertise and help you provide better care for these amazing pets.


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