Home / Aquarium Fish / Bettas / Current Page
Close-up of betta fish in tank

Do Betta Fish Need a Filter? Filtration in Betta Tanks

Through my years of fishkeeping experience, I’ve discovered that certain fish require filtration more than others, So what about betta fish?

Quick Answer

 Although the common misconception is that betta fish do not require a filter, this is simply not true. Just like any other fish, a betta fish requires a good filtration unit to keep the aquarium water clean and clear, to allow for a healthy and happy life.

Keep reading to find out everything there is to know about betta fish and their aquarium filtration requirements.

A Common Misconception – Betta Fish Don’t Need Filters

One of the most common misconceptions in the fishkeeping community is that betta fish do not require any kind of filtration in their aquariums. Now, what I want to do is to touch on exactly why this misconception exists at all.

Close-up of betta fish in tank

The reason why many people think that betta fish do not require any filtration is because in the wild, they often live in very shallow, dirty, and muddy water

Betta fish most often live in very shallow puddles, often in rice paddies. At certain times of year, these rice patties dry up for the most part, leaving behind relatively thick and muddy water, which betta fish seem to be fairly happy living in.

People see or hear about this and then think that their betta fish does not require any filtration, because after all, they live in such conditions in the wild. However, just because the water in a betta fish’s natural environment is a bit muddy, it doesn’t necessarily mean that it’s dirty or full of contaminants.

Furthermore, just because a betta fish can survive in such conditions does not mean that it is preferable, especially over a prolonged period of time. What it really comes down to is that for a betta fish to be happy and healthy and a home aquarium, decent filtration is required.

Do Betta Fish Require Filtration?

The simple answer to this question is that yes, a betta fish in a home aquarium requires some decent aquarium filtration. There are actually various reasons for this.

First and foremost, if you don’t have a good filter for your betta fish, all of that ammonia and nitrites will build up in the water, and that’s not good for your betta fish. You see, when your betta fish eats food and then leaves some of it behind, as well as when it excretes waste, it will cause an increase in ammonia and nitrite levels.

These are poisonous compounds for your fish, ones that can kill your betta fish within a very limited amount of time. If you don’t have a good filtration unit to remove both the solid organic matter, as well as the resulting ammonia and nitrites, your betta fish won’t survive for very long.

There are also other contaminants that may be present in the water which are not good for your betta fish, especially over the long run, ones such as heavy metals that may come from your tap water.

What it really comes down to is that if your betta fish is living in extremely dirty water, in one way or another, it will most likely die.

If it’s not the actual ammonia that gets your betta fish, it might just be the stress caused by living in poor water quality. Remember, fish like betta fish can get stressed out very easily by things like poor water quality, and when they do, their immune systems take big hits. This leaves them vulnerable to a variety of diseases and infections that are possible in any home aquarium.

What Happens to a Betta Fish Tank Without Filtration?

So, let’s assume that you decided not to get a filtration unit for your betta fish tank. What’s going to happen?

  • If you don’t have good filtration for your betta fish tank, all of that uneaten fish food, old plant matter, and fish waste will build up in the tank. At the very least, this just doesn’t look very nice as it will make the water look cloudy and dirty.
  • If all of that fish waste and uneaten fish food is left in the fish tank, they’ll start to release ammonia and nitrites, which can quickly kill your fish. This is usually referred to as ammonia poisoning, and it quite literally burns your fish from the inside out. It doesn’t take very long for excessive ammonia levels to kill your fish.
  • Even if the ammonia itself doesn’t kill your fish, all of that contamination in the water will cause stress for your betta fish. If your betta fish gets stressed out, its immune system will take a hit, and it will likely develop diseases, which can then quickly lead to death.
  • If you eat too much organic matter in the fish tank, you’ll end up providing algae with the perfect food source to bloom. More often than not, dirty fish tanks then also suffer from algae blooms.
  • At the very least, if you don’t properly maintain your fish tank through filtration, you’ll have to clean it much more and perform more water changes on a regular basis. You might think that this is more than enough to make up for the fact that you don’t have a filter, whereas the simple reality is that constantly moving your betta fish out of the tank to clean it is also not ideal.

What Kind of Filtration do Betta Fish Need?

Now that we know that betta fish need filtration, let’s take a closer look at the three main types of water filtration that you need for any home aquarium, whether for a betta fish or otherwise.

The first type of filtration is known as mechanical filtration. This often consists of filter pads, floss, and sponges. This type of filtration is designed to remove physical debris from the water, things like fish waste, rotting plant matter, uneaten fish food, and so on and so forth. This is very important because it helps to prevent these materials from rotting and degrading in the water, therefore preventing the release of ammonia and. It also makes the water much less cloudy.

The second type of filtration necessary in any fish tank is known as biological filtration. For biological filtration, this is performed by a colony of beneficial bacteria. These are bacteria that take ammonia and nitrite and break it down into nitrate, a substance that is much less harmful to your fish. 

This way, even if your mechanical filter is not able to remove all organic matter from the fish tank, at least the biological filtration aspect can then make up for it and remove any remaining ammonia.

The third type of filtration you need for any fish tank is known as chemical filtration. This often comes in the form of activated carbon or charcoal, and it is designed to remove a variety of unwanted substances from the water. 

This includes, but is not limited to, heavy metals, chlorine, pesticides, and other such things. If you have all three of these filtration types, your betta fish should do just fine.

How Strong Should a Betta Fish Filter Be?

When you go to buy a fish tank filter, you might see that it is labeled as having a certain flow rate in gallons per hour. Generally speaking, for a fish tank to be as clean as possible, you want that aquarium filter to be able to process at least three times the total amount of water in the tank per hour.

This means that if you have a 5 gallon betta fish tank, your aquarium filter should be able to process at least 15 gallons per hour. However, there are also much more powerful filters out there that can process much more than that.

For instance, some of the best aquarium filtration units out there can process up to seven or eight times the total water volume in the fish tank every single hour. This of course results in extremely clean and clear water that every and any betta fish would be more than happy to live in.


There you have it folks, you should now know virtually everything there is to know about betta fish tank filtration.

Was this helpful?

Thanks for your feedback!

Enjoyed? Spread The Love

Table of ContentsToggle Table of Content