How To Clean A Betta Fish Tank | A Maintenance Guide

A partial water change and scraping off some algae is about all you need to do at any one time. You do not have to clean the whole tank and everything in it. Ever.

If you’re thinking of getting a betta, it’s good that you are here researching just what is involved in cleaning a betta aquarium. Once you have a new tank up and running, doing routine maintenance is crucial to keeping not only a healthy tank but a tank you do not have to put much time into cleaning.

Equipment Needed

The most important thing you need to remember about equipment for cleaning a betta tank (or any fish tank) is to only use that equipment for cleaning tanks. You never want to mix it up with house cleaning equipment, as residual cleaning chemicals can kill your betta.

You need:

  • A bucket
  • An algae scraper
  • A scrub brush safe for aquariums 
  • A gravel cleaner.

Stick one end of the gravel cleaner into the tank and suck on the hose. This gets the water moving. Place the dirty water in a bucket. Move the gravel cleaner around in the corners to get pockets of fish poo and old food. Cleaning anything else is optional. Replace the dirty water with clean, treated water.

Cleaning a New Betta Fish Tank

It’s always best to get all the equipment you need to keep a betta, like the tank, at least one month before you bring a betta home. This way, you not only know that everything is working, but that the tank has taken long enough to be properly cycled.

You do not need to use any special cleaners with a brand new, just-out-of-the-box betta fish tank. In fact, you do not need any cleaners at all. Just rinse well with hot water. It’s also good to fill the tank with water and leave it for a day to check for any leaks.

About Used Aquariums

My best fish-keeping experiences have been with used aquariums. They were all from my Dad. When he decided to move to what would be his final home, he decided he could not bring his two aquariums, so I took them. 

That being said, I do not recommend getting a used fish tank if you do not know the tank’s history. The tank could have been used to house animals other than fish. Some people have had success using tanks that once housed small animals, but I have not.

Back in the 1990’s, I was told by other fish keepers that it was impossible to get animal urine out of the sealant used in aquariums. I have not found any proof that this happens. All I know is that when I tried to keep fish in an aquarium that used to hold guinea pigs, all of the fish died within a week, even after I took time to cycle the tank.

How Often Should You Change the Filter Media?

You do not always need to change the filter media as often as the manufacturer suggests. The filter retains some of the healthy bacteria necessary to keep your betta alive. A sudden change could lead to a spike in bad chemicals like nitrite.

Only change the filter media when the water starts getting cloudy, or if your filter is getting so blocked by gunk that it can no longer filter the water. 

One thing you definitely do not want to do is remove the filter from the tank, dunk the dirty filter in bleach to clean it, and then place it back into the filter. The leftover bleach on the filter will kill all of your fish and any live plants in the tank. This (hopefully) might seem like a no-brainer, but I’ve heard about people doing this – and then wondering why all their fish died.

Cleaning Algae from Your Betta’s Tank

All fish tanks grow algae. A little is good for a tank, because it helps to clean the water. However, the algae should not overtake the tank. If you look at your tank and can only see algae because it’s coated every inch of the glass walls, then you’ve got a problem.

Okay – I exaggerated a little. Still, algae should not grow so much that it sticks up in long fronds and waves at your betta when he or she swims by. 

Get an algae scraper. Scrape the algae off of the aquarium walls, the heater, and the air stone. This will leave a lot of loose algae floating around. Now is the time to do a partial water change. This helps get rid of the loosened algae.

It’s normal for the water to be cloudy right after this water change. As long as your filter is working well, the water should clear up in a day.

You do not have to scrub all of the algae off of the decorations. If one decoration is completely coated, then take it out of the tank when you do your partial water change. Place it in the dirty water you just removed from the tank. Use a brush that you only use for this purpose. Scrub and rinse off the decoration in the aquarium water. Never use any cleaner, because that may kill your betta.

In fact, you never clean off all of the tank’s algae at one time. Good bacteria that help change harmful chemicals to good ones sit on surfaces on the glass and on the decorations. Cleaning everything at once will kill off all of the good bacteria.

The Importance of Partial Water Changes

The most important thing you can do to keep the water clear, to cut down on algae growth, and for the health of your betta is to do regular partial water changes. Only about 10 to 25% percent of the water needs changing at a time for a healthy tank.

How often you do partial water changes depends on how large your betta’s tank is. The larger, the less often you have to do it. One adult betta kept in a 3-gallon aquarium needs a water change every couple of days. One betta kept in a 10-gallon aquarium needs a partial water change about every two weeks.

Keep in mind that a filter will keep the water clean for a longer time allowing for fewer water changes.

There’s no hard and fast rule about how often to do a partial water change. See how the tank looks. Is there a lot of fish poop about? Is it time to scrape more algae off of the walls? Then, it’s time for a partial water change. 

When to Do a Complete Water Change

Try to avoid 100% water changes at all costs, since the shock of completely new water can kill your fish. Now, if all of your fish have died, then, by all means, time for a complete change.

The only other time to do a complete water change is if, for some reason, you have to keep your betta in a one gallon or smaller container, perhaps if you need to keep him or her there because the other tank sprung a leak and you haven’t been able to get a new tank yet.

The Least You Need to Know

All you need to clean a new aquarium is water. Like all things in life, cleaning your betta’s tank is best done in moderation. It is possible to clean a tank too much. Fish need a good number of healthy bacteria in their tanks to keep down dangerous levels of toxic chemicals like ammonia and nitrite. The most important thing is to do regular partial water changes.

If you want to learn more about betta tanks, please visit our collection of articles here.

About the author

Hi, I am Rena.
I grew up in a house surrounded by fish tanks.
I have spent my life caring for and writing about fish.
I have studied journalism and worked for online and print magazines.

You can find the articles I wrote here