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Cleaning a betta fish aquarium

Betta fish might be small, but they still require a sizable amount of care. If you’re going to keep this type of fish, you must learn how to clean a betta fish tank. 

Even with a quality aquarium filter, betta tanks can become overwhelmed with nitrates and other toxins if you don’t clean them and partially change their water regularly, which can ultimately be fatal. 

Keep reading to learn all the steps involved in cleaning a betta fish tank, plus some other helpful information to make the process go more smoothly. 

How often should you clean a betta fish tank? 

Tetra ColorFusion Aquarium 20 Gallon Fish Tank Kit

This depends on the size of your tank and the setup. You should never keep a betta fish in a tank any smaller than 5 gallons, but larger is better. Something between 15-20 gallons, such as the Tetra ColorFusion Aquarium, is ideal for a betta fish and a handful of suitable tankmates. The main benefit of a larger tank is that it provides a more enriching environment for your fish, but it comes with the added bonus of less regular cleaning. You need to clean a 5-gallon tank weekly, while a larger 15- or 20-gallon tank only needs cleaning once or twice a month.

Should you remove your fish from the tank while cleaning it?

Penn Plax Aquarium Fish Net

Ideally, you should keep your betta fish in the aquarium while you clean it because removing them can stress them — only remove them if you’re changing 80% or more of the water in their tank. In this case, carefully remove them with an aquarium net and place them in a bowl or large mug with plenty of water from their aquarium, making sure to cover it with something breathable.

Should you clean the filter at the same time as the aquarium? 

Tetra Whisper IQ Power Filter

Your betta tank needs an aquarium filter, such as the Tetra Whisper IQ Power Filter, but you shouldn’t clean it or change the media at the same time as you clean your tank and change the water. Filters are full of beneficial bacteria colonies that help create a healthy tank ecosystem, so changing them at the same time as the water can wreak havoc. 

Preparing to clean your betta tank

Wash your hands and put on gloves 

Before you get started cleaning your betta tank, wash your hands and put on a pair of disposable gloves. This protects you from bacteria in the tank and the tank from any bacteria or germs on your hands.

Prepare fresh water 

Tap water is full of chlorine and other substances that can be toxic to fish, so you need to prepare the clean water you’re going to put in your aquarium ahead of time. Fill a clean bucket with as much water as you need and add a commercial aquarium water conditioner according to the package directions. Alternatively, you can simply leave the water uncovered for 24-48 hours, which is long enough for the unwanted substances to disperse.

Turn everything off 

Your betta fish tank should have a heater and filter. Turn these off before you start cleaning, along with any other electrical items, such as lights and bubblers. 

Steps to clean a betta fish tank

Remove algae 

Use an algae scraper to remove any algae you see growing inside the tank. There are different types of algae scrapers for both glass and acrylic tanks, so choose accordingly to avoid scratching or damaging the aquarium. 

Clean gravel and siphon water

Use a gravel vacuum or gravel siphon to clean the gravel substrate of your betta fish aquarium. Dropped food and fish waste can settle in the substrate and breed bacteria, so it’s important you clean it. Gravel siphons clean gravel and siphons off the water at the same time. You’re doing two jobs at once — cleaning the substrate and removing the water that you’ll replace with your clean prepared water. In a betta tank of 10-20 gallons, you should aim to remove 10-20% of the volume of water in the tank. In smaller 5-gallon tanks, you may need to remove more like 30-40% since more waste builds up in a smaller area.

Remove and clean tank ornaments

You don’t need to clean ornaments every time you clean your betta fish tank, but look out for algae buildup and clean them when necessary. Remove the ornaments from the tank slowly and carefully so you don’t stress your fish and clean each one with hot water and a clean toothbrush. Avoid using soap or cleaning products as these can be toxic to fish. 

Refill the tank

Slowly refill the tank with the water you prepared earlier. You should have left it out long enough for the water to reach room temperature, though if you’re doing a large water change, you should gently heat it to the same temperature as the water in the tank — this should be 75-80 degrees for betta fish.

Turn everything back on

Now that the tank’s clean and topped up with fresh water, it’s time to turn your filter, heater and any other electronic items back on. 

What you need to buy for cleaning a betta fish tank

API Algae Scraper

API Algae Scraper

Used for cleaning the algae off the inside of an aquarium, this is a must-have when cleaning your betta fish tank. It should be used only on glass and not on any other surface.

Where to buy: Sold by Amazon and Chewy

Python Pro-Clean Gravel Washer and Siphon Kit

Python Pro-Clean Gravel Washer and Siphon Kit

This device cleans aquarium gravel while siphoning off water, getting two jobs done at once. It is suitable for aquariums with a capacity of 20 to 55 gallons.

Where to buy: Sold by Amazon and Chewy

LEAKTITE 500 5-Quart Plastic Pail

LEAKTITE 500 5-Quart Plastic Pail

A simple pail that you can use to collect dirty water from your tank. It’s large enough to do a 20% water change of a tank up to 25 gallons.

Where to buy: Sold by Amazon

API Tap Water Conditioner

API Tap Water Conditioner

This water conditioner neutralizes chlorine and other substances in tap water that can be toxic to fish, making it safe to use right away. It should be used whenever you add a fish or water to the aquarium.

Where to buy: Sold by Amazon and Chewy


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