How Long Can an Aquarium Filter Be Switched Off?

New tank owners may often wonder if they can turn off their aquarium filter. They may wish to do this for many reasons, so here we will dive in to find the answer.

How long can an aquarium filter be switched off? Aquarium filters are designed to run 24 hours per day, seven days a week, and in most instances, that is the amount of time you should aim to run your aquarium filter to avoid problems. Filters agitate the water while filtering waste and uneaten fish food from the tank. An aquarium filter is also home to many thousands of beneficial bacteria that help keep fish tanks healthy.

Can I Turn My Aquarium Filter Off at Night?

Most fish tank owners anticipate turning their filter off for 8 to 10 hours when they ask about turning the filter off at night. If the nights were intermittent and not too often, then based on fish numbers and tank size, it could be possible to leave the filter off on rare occasions.

However, by doing so, you put fish at risk. You won’t have water agitation, and the beneficial bacteria that live in the filter will soon start dying. Without these bacteria, the amount of ammonia will increase, which is one of the most harmful elements to the aquarium and your fish.

Can Fish Survive Without an Aquarium Filter for One Day?

Fish can survive without a filter running for one day, and you could face this if there is a power outage. If you have power and you need the filter off, or it has broken, and you need a replacement, it would help to have an air stone running in your aquarium.

Bubbles from the stone will introduce oxygen, yet if you also have a water heater, this area can become too hot as your filter won’t be dispersing the warm water.

Why Do I Need to Run My Aquarium Filter All the Time?

Ideally, we have seen you need to run your aquarium filter all the time to maintain the health of the tank. Here are the principal reasons it is vital to have a running filter all the time.

Beneficial Bacteria

In your aquarium, live beneficial bacteria can be found near the aquarium filter.

The beneficial bacteria are responsible for keeping the environmental parameters under control, which keeps all the aquarium inhabitants alive, healthy, and comfortable.

It’s critical to understand how to clean an aquarium filter properly, or you’ll kill the beneficial bacteria, effectively pushing the water quality parameters out of the ideal setting and endangering your fish’s lives!

Temperature Regulation

Keeping your filter on all the time makes it easier for the water heater to control the temperature of the water. Some fish types are more resistant to temperature changes than others. So, if temperature swings are too significant and frequent, some fish would become stressed and die prematurely.

Water Agitation

In a healthy tank, agitating the water is a necessary process, and the way you agitate the surface is by using filters. It aids gas exchange when all this occurs. When carbon dioxide is released from the water, oxygen enters the system. This facilitates maintaining a healthy tank. Even though living underwater, live plants and your fish require oxygen.

Water Movement

Some floating debris and organic materials are removed from the water by filters. Excess food and fish poop are the most common occurrence.

This means these organic materials still need to be removed from the filter. Although they have been removed from the tank’s central portion, they are still in the same water, flowing from the tank to filter and back again.

Air stones can help with water agitation, yet you won’t find they help with being a home for the beneficial bacteria or maintaining a constant water temperature.

Do Aquarium Filters Use a Lot of Electricity?

In most instances, besides any products for the maintenance of your aquarium, specific components use power and should remain on for most of the time. Lighting and heaters are in the group with air pumps and your water filters.

Here you can find out how much power your filter can cost to run. If you use a 10-gallon aquarium as an example, this could consume around 150KWh per year to run at a steady temperature of 72°F.

It may appear to be a lot, yet you need to look in more detail where these costs are proportioned.

Aquarium lighting can equate to around 45 per cent of the power consumed. Aquarium heaters follow by using about 35 per cent of the power.

Once you see how much power your filter uses, it pales compared to these two as they only consume around 12% of the power. For the year, this calculates to around 18KWh. Turning a filter off to save electricity isn’t a principled reason since they consume so little.

Can I Make My Aquarium Filter Quieter?

Another of the more common reasons tank owners wish to turn off their filters is because of the noise. Rather than put your fish at risk, it is better to resolve the issue of what is causing the filter to be noisy.

The buzz or rattle you hear may come from anywhere since aquarium filters come in various shapes, sizes, and power ranges. Besides this, not every noise you hear can come from your filter, so isolating the sounds is the only way to be sure.

Given the technological advancements, most filters are relatively quiet, but as they agitate the water, the splashing noise can irritate some people. 

You may discover the sounds are usually louder as the intake nozzle clogs from algae or other debris. As an aside, this will affect your filter’s performance. If this is the case, it is a sign you need to clean your filter.

Are There Any Fish That Live Without Filters?

It is possible to have fish where you don’t need filters. However, there is an increase in care and maintenance associated with these types of fish.

The other thing to note is, such fish may be solitary rather than selecting several fish for your tank.

Here are the main fish that can survive without an aquarium filter.

  • Betta Fish
  • Ember Tetras
  • Guppy Fish
  • Pea Puffer Fish
  • Scarlet Fish
  • Zebra Fish

The fish here are kept in large jars or bowls rather than a full-sized aquarium. The fish are also cold water and don’t need the help of a heater. The most significant thing for care is you may need to change the water every day to remove toxins and waste.


With all the above, you can see that you shouldn’t aim to turn off your aquarium filter besides the time to clean the filter. Depending on the type, it may be carried out on a more regular basis than others.

Most filters require cleaning every 4 to 6 weeks and can take a few minutes to no more than an hour. This amount of time without a filter won’t harm your fish, especially if you run an air stone in your tank.

Filters are the most vital part of your aquarium and are the one area you shouldn’t be looking to change.