How To Clean A Betta Fish Tank (And How Often)

Have you just bought a betta fish, or are you thinking of buying one soon? If the answer is yes, then you might be wondering exactly how, as well as how often to clean your betta fish tank.

Well, it depends on the size of the tank and how many animals you have in the tank.

Keep reading and we’ll show you everything you need to know about cleaning a betta fish tank.

How Do You Clean A Betta Fish Tank?

It’s not hard to clean your betta fish tank and shouldn’t take you more than 15-30 minutes.

Use An Algae Pad

Before removing any of the water, you’ll want to scrub off any algae. Algae may show up if your tank is getting too much light, or if there is too much leftover food breaking down.

Pet stores sell cheap algae pads. You can use these to scrub the side of your tank and the decorations to remove the algae.

You can also get a soft algae brush to get into the hard-to-reach-places of your decorations.

Change The Water

Next, you’ll need to change the water. NEVER remove all the water from the tank. This can shock your betta and possibly restart the nitrogen cycle.

Instead, remove about 25% of the water with each water change.

Use A Gravel Vacuum Or Pipette

Gravel vacuums are great for removing leftover fish food and waste that gets stuck in the gravel. The vacuum creates a suction that pulls the water and waste out of the tank. These are great for larger tanks, but they work for five to ten-gallon tanks as well.

For tanks smaller than five gallons, you should use a large pipette. They work similarly to a gravel vacuum, but it takes a bit more work on your part.

Add New Water

Lastly, you’ll need to add in fresh water to replace what you’ve taken out. It’s best to prepare this water the day before if possible. Make sure that the water is at a similar temperature to the water you’ve removed so you don’t shock your fish.

Use A Chlorine Neutralizer

If you’re filling your aquarium with tap water, you’ll need a chlorine neutralizer. A great option is API’s Stress Coat. It neutralizes chlorine and heavy metals to make tap water safe for your fish.

Clean Or Change The Filter

How you clean the filter depends on which kind of filter you have.

Sponge filters work best for bettas. They have gentle flow, they hold bacteria well, and they’re easy to clean.

To clean a sponge filter, remove a bit of the aquarium water and place it in a bucket. Gently shake the sponge into the water in the bucket to remove the debris. Don’t scrub too hard, and don’t use tap water to clean the sponge. Doing so will kill the beneficial bacteria that has built up inside the sponge.

If you have an over-the-tank filter, cleaning will be a bit different. As for the filter itself, you can gently wipe down the outside with a damp washcloth. This will remove any unsightly spray residue.

Over-the-tank filters will also contain filter media. Most filters designed for betta fish tanks will use filter cartridges. Filter cartridges are pre-made bags that contain active carbon and sometimes other ingredients.

You simply need to throw these filter cartridges out once a month, then, replace the cartridge with a new one.

How Often Should You Clean Your Betta Tank?

Generally speaking, you should clean your aquarium once every one to two weeks. Some tanks need cleaning more often than that. Other aquarium keepers can get away with only cleaning once a month.

Because bettas are usually kept in smaller tanks, once every week or two is your best bet.

How Big Is The Tank?

The smaller the aquarium, the more often you’ll need to clean it. Smaller aquariums build up waste and leftover fish food more quickly. If you don’t clean the tank, an ammonia spike may kill your fish.

Hopefully, you have at least a 5-gallon tank with a filter for your betta. If that’s the case, you can clean your tank about once a week. If you have a 10-gallon tank or larger, you may be able to go every two weeks.

It’s not recommended to keep bettas in anything smaller than a 5-gallon. But, if you do have your betta in a smaller tank, you’ll have to clean their tank even more often. You’ll need to clean a smaller tank about two to three times a week.

Beginning fish keepers who don’t know better may keep their betta in a one-gallon tank or smaller. These tanks almost never have a heater. If this describes you, we really recommend upgrading your tank. It’s what’s best for your fish.

But, if you can’t upgrade the tank for whatever reason, you’ll need to clean the tank every one to two days.

Does Your Tank Have A Filter?

Many people make the mistake of believing that betta fish don’t need a filter. But, every fish tank should have a filter.

A filter helps to remove waste and keep the aquarium clean.

If you have a filter, then the time frame above still stands. Cleaning once every one to two weeks is usually good.

If you don’t have a filter, you’ll need to clean even more often. Without a filter, you’ll need to clean the tank every two to three days.

Are There Any Tankmates?

Likewise, if your betta is the only inhabitant of your tank, cleaning every one to two weeks will work fine. If you have other animals in the tank, you might need to clean more often.

One to two weeks works great even with a lot of fish. That is, if the tank is large enough, isn’t overcrowded, and has good filtration.


How often you clean your betta fish tank depends on the size of the tank and how many animals you have living in it. Smaller tanks need cleaning more often than larger tanks.

But for a general rule of thumb, if you want to keep your betta fish happy, clean their tank once every one to two weeks following our guidelines.

Don't forget to check out