How to Clean a Betta Fish Tank in 10 Easy Steps

To ensure your pet betta stays healthy and lives a comfortable life, only providing them good food isn’t enough. Betta fish are low maintenance aquarium fish, but like other fish, they will leave various waste in the tank water, so cleaning it from time to time is vital.

Bettas need a clean fish tank without toxins or other chemicals to avoid getting sick. A betta tank full of toxins food waste can cause diseases like fin rot or fin melt in addition to internal diseases.

Here is the complete guide on how you can clean a betta fish tank so that your fish does not have to suffer in the tank water.

What you need to clean a betta fish tank

A macro picture of a fish tank with some rocks and some plants.

You will need some basic tools to clean the tank properly. Here is a list of equipment you can easily find either in a pet store or online.

A gravel vacuum

The gravel vacuum will suck out the uneaten food or other waste material gathered at the bottom of the betta fish tank.

Large bowl

You can’t clean the tank with the fish inside it. So take a small bowl but be comfortable enough to keep it during the tank cleaning time.

Algae scrubber

Algae growth is common in betta fish tanks, and if it goes unnoticed, it can ruin the whole water quality. With an algae scrubber, you can keep the aquarium clean and algae free.


A blade can come in handy to scrap off excess debris from the tank glass or the aquarium decorations.

Water conditioner

When you change aquarium water while cleaning the tank, you will need a water conditioner to make the fresh water safe for your betta fish. Adding unconditioned tap water is again harmful to fish which may lead to skin diseases.

Room temperature water

Allow the new water to sit for about 24 to 48 hours before adding it into the aquarium. Keeping the water at room temperature removes harmful chemicals, making it safer for the betta fish.


If you have tank decorations inside the tank, you’ll need to clean those as well. A toothbrush is the best option to get the debris off from your tank decor.

Fish net

The fish net helps safely remove the betta fish from the tank before you start the cleaning process.

Cleaning your betta’s tank: step by step guide

Hand pumping out water from a fish tank for cleaning purposes.

Get a bucket of water to sit for 24 hours

It’s best to let your tap water sit for 24 hours at room temperature before adding it into your betta’s tank, so the day before you plan to clean, get your water ready.

Clean your hands first

Germs can enter the fish tank through dirty hands too, so ensure you clean your hands well with warm water and soap. Make sure the soap is washed off your hands as soap residue in the fish tank is poisonous for betta fish.

Remove the betta fish

Next, use the fish net to remove the betta from the fish tank and transfer it to a small tank or bowl (filled with the same water from their tank). The fish may try to jump out of its new home so keep a cover on the top (betta fish love to jump)!

Unplug everything

Unplug all electrical items like the water pump, lights, heater, filters, or any other electric equipment you have inside the aquarium. Keeping everything unplugged ensures you don’t get electrocuted.

Remove decorations

After removing the betta fish and unplugging all electrical items, it is time to remove decorations. These decorative items all get dirty over time, and cleaning them is as important as cleaning the rest of the fish tank.

Use the toothbrush and warm water to scrub off any extra dirt or debris from these decorative pieces. Bettas use these as hiding places, and keeping clean decorations is important to maintain a healthy betta.

Scoop out old water

An important step of cleaning the betta fish tank is scooping out the old water. You need to change 30% to 50% of the water from the betta aquarium every week (if you have a tank filter, you only need to change 20%). But don’t make the mistake of changing the whole water at a time.

Keep the old water into a bucket, as you will have to add it back into the aquarium once you are done cleaning. Don’t worry about adding dirt or waste back with the previous water, as most wastes remain in the tank bottom.

You can dump the remaining water down the drain as you don’t need it anymore.

Remove pebbles

After emptying the aquarium of dirty water, you now need to remove the pebbles from it. Pebbles can collect a lot of algae, so they also need a thorough cleaning. You can use the toothbrush as a soft scrubber for these pebbles.

Replace/clean the filter media

After removing the water and pebbles, clean the filter as it collects a lot of dirt as well. But it’s better not to clean the filter with fresh water as it can remove beneficial bacteria from it. So you should wash it with the tank water itself.

Put the gravel vacuum to use

The gravel contains the most dirt build-up; hence cleaning it is an extremely important step. Turn on your gravel vacuum and run it all around the corners. The vacuum will collect all the debris lying inside the betta fish tank. Additionally, the gravel vacuum will also suck out any remaining water.

Clean algae

Algae is very common in fish tanks. So to clean it, use an algae scrubber and rub it all over the aquarium walls. Run the scrubber on all corners of the aquarium wall to get rid of all the algae. If the scrubber has got too much algae, rinse off the scrubber in between cleaning.

If the algae build-up is too much, use a razor and run the edge of the razor along the tank to scrape off the algae. Additionally, you can use an abrasive sponge.

Clean the tank

Till now, we have cleaned parts and pieces of the aquarium. Now its time to wash the entire container. Acrylic tanks need special care as they are prone to scratch. Remove any tiny particles of the pebbles or stone with a paper towel.

After taking out any shards of the stones or pebbles, put the tank under running water and begin scrubbing it with a clean sponge. Repeat the process a couple of times to clean the slime. You can use a fish cleaner as well for this process but rinse the residue well by rinsing the dirty tank multiple times.

This was the last step to get a completely clean container for your betta fish. Neat and clean surroundings will ensure a happy fish with other aquarium inhabitants.

Time to reassemble the clean tank

Once you are done with the cleaning, its time to reassemble the tank just like it was before; rearranging won’t take much time, and with just three simple steps, you can give your betta its old house back.

Add water to the aquarium

Remember that water from yesterday that has sat for 24 hours? Time to get it. Remember: you aren’t filling your tank up with 100% new water and should still have the old water reserved.

Add water conditioner to the tap water to remove chlorine or any other toxins. Additionally, you might have to treat the tap water to get the right pH level to 6.8-7.5.

Add both these waters into your tank.

Adding back the decorations

After adding water, it’s time to reinstall the clean decorations in the filtered tank. Keep them as they were before. Finally add all electrical items, including lamps, heater, fillers, and other equipment.

Make sure the water gets up to the right temperature before adding your betta fish into the tank. Betta fish like water temperatures of 75 to 80 degrees F.

Put the betta fish back in the tank

Take the betta fish in a small cup and tilt it slightly inside the tank. The betta will go inside the tank on its own. Be gentle and make sure you don’t dump your betta fish in from high up in the air.

How often should you clean your betta fish tank?

To keep your betta fish healthy—and your tank looking great—water change and tank cleaning at regular intervals are necessary. But hobbyists most often struggle with the question of how often they should clean a betta fish tank.

Water change depends on conditions like feeding habits, filtration, tank size, water circulation, and water quality.. Generally, you should change 20% of the water every week to clean your betta bank of any toxic substance.

As for full tank cleanings, you should do those every 6-8 months.

If you regularly clean a betta fish tank, the water quality will remain high; there will be less debris less algae growth, and the toxin growth won’t reach a limit where it can harm the fish.

Why is cleaning a betta fish tank important?

Bettas are tropical fish, so their natural habitat includes:

  • Constant importation and exportation of minerals.
  • Good bacteria.
  • Balanced pH levels due to the frequent water flow.

Fish tanks can’t introduce these substances on their own, so you need to mimic a betta’s natural environment as best as you can, which you can do through regular cleanings.

If you keep the fish in dirty water for too long, the fish will suffer from skin disease, appetite loss, stress, to name a few. Bettas can quickly catch infections if kept in unhygienic surroundings; therefore, if you want to see your pet fish live a healthy life, don’t skip regular betta tank cleaning.

Wrapping up

Betta fish are relatively easy to care for once you know what they need. To keep your betta fish healthy, make sure to change their water regularly and clean their tank every 6-8 months.


Why is my fish tank getting dirty too soon?

Common reasons your fish tank water gets dirty too soon are uneaten food and debris build-up, your filter is too small, you don’t clean it frequently, there is excess algae formation, and you are not changing the water regularly.

Can I use tap water in the betta fish tank?

You can use tap water in the betta tank, but you need to dechlorinate the water and leave it at room temperature for at about 24 hours before adding it to the tank.

How often should I clean my betta fish tank?

You should clean your betta’s fish tank every 6-8 months.

Richard Parker

Richard is an avid aquarist and has been keeping betta fish and other freshwater fish since he was a young boy. Through Aquatic Buddy, he hopes to help others learn how to care for their betta fish so they thrive in their home environments.

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