Best Filter for Betta Fish

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We know that keeping a Betta in a small cup or container is not optimal. Like all fish, the Betta benefits from having the proper water conditions which can be greatly affected by whether your tank is filtered or not.

Today, we are going to take a look at the best filters for Betta fish, so you can make an educated purchase when it comes to the health of your pet. 

My top choice? 

The Nicrew Internal Aquarium Filter. Check it out!

blue betta fish

Here are the filters I will be reviewing:

Reviews of the Best Filters for Betta Fish

Don’t have a clue of the best filter for Betta fish? Here are some you may want to consider. 

Nicrew Internal Aquarium Filter

Even though the Nicrew Internal Aquarium Filter is gentle enough for your delicate Betta, it still offers superior tank cleaning through activated carbon and a fine filter foam that traps debris, absorbs odor, and provides a biologically stable environment for all aquatic pets.

Another great feature of this filter is the adjustable air regulator. The spray bar sits above the waterline creating a natural “wave” effect that also aerates the water. If you have fragile fish (like Bettas or shrimp) you can adjust the airflow or move the bar so it is directed toward the side of the tank creating an even smoother environment.

This unit also comes with sturdy suction cups to keep it firmly anchored in the tank and is low noise, so it won’t be keeping anyone awake at night.

Lastly, the Nicrew is also available in three sizes (suitable up to 40 gallons) and can be used in both fresh and saltwater aquariums. However, it is not recommended for aquariums under 5 gallons as it may be too powerful for Bettas in a tiny setup. It is also fair to note that some customers have complained that the unit was a bit noisy and was difficult to clean. 


  • Provides optimal biological and chemical filtration
  • Carbon can be replaced with different filtration media
  • Foam only needs to be rinsed (not replaced)
  • Quiet, yet powerful
  • Adjustable spray bar (for direction and flow output) 
  • Great for providing oxygen in the tank
  • Quick assembly and disassembly
  • Fully submersible


  • Not recommended for tanks under 5 gallons
  • May be difficult to clean 

Upettools Biochemical Sponge Filter

This filter may be odd-looking but that’s because of the 7-layer sponge design which can quickly improve the water conditions in established tanks, as well as create the coveted biological layer (known as biofilm) where those healthy microorganisms can attach and grow. 

Nestled below the ribbed sponge are ceramic media balls that work in conjunction with the filter to purify the water, help add oxygen, and also support the biofilm. These never need to be replaced; just a quick rinse when it becomes dirty is all that is needed. You may also choose to use carbon in this layer that can be purchased separately.

The Upettools Biochemical filter also has a 360-degree rotating head, so you can change its height to suit your aquarium and point it in any direction for delicate Bettas. This unit also comes with two suction cups to clamp it firmly in place and is also available in a double-sponge for extra filtration.

Do note that some customers find this filter too big for tanks under 5 gallons and may not be as effective in large aquariums (50 plus gallons). The green sponges are also more useful (compared to the black ones) in determining when they need to be rinsed off and the ceramic balls may clog up the water flow on occasion. You will also need to purchase an external aquarium pump and tubing to run the Upettools filtration system.


  • Quickly creates a biological layer while it purifies and oxygenates the water
  • Gentle enough for delicate fish
  • Uses a 7-layer ribbed sponge for filtering out fine impurities
  • Ceramic balls never need to be replaced just rinsed
  • Sponges are available in both black and green (color is the only difference)
  • 360-degree directional spout
  • Petttools sponge filter is available in single or double-sponge models


  • Needs a powerful air pump and tubing (not included)
  • Ceramic balls may clog up water flow
  • Not suitable for tanks under 5 gallons

AquaCity Corner Filter

Most Bettas are kept in smaller aquariums, so we’ve found a filter that works well in those cozy habitats (10 gallons and under). 

The AquaCity Corner Filter uses a three-layer system that, not only, purifies and oxygenates the water, but also helps create a biofilm. This is done through the use of gravel and ceramic rings (bottom), a black bio sponge (middle), and a coarse white sponge (top). The great thing about the filtering media in this unit is that you only need to rinse it out!

The filter itself is quite quiet, just watch what type of air pump you attach to it as that could become a noise source. It is also good to note that some customers complain about the unit floating, but a quick fix of using a small rock on top of it or wedging it into the corner took care of the issue. 

This filter does create bubbles (perfect for aeration) and is gentle enough to use with Bettas, shrimp, and snails. However, some buyers did notice that air was building up inside the filter, creating huge air pockets, so take note over the first few days of usage to ensure your unit is bubble-free.

Overall, the effectiveness of this cute little filter is favorable, especially when using it in a small aquarium, or tandem with a larger unit. 


  • Great for 3 to 10-gallon aquariums
  • Filtration medium rarely needs to be replaced and creates a good biofilm
  • Creates bubbles for added aeration
  • Reasonably priced
  • Gentle enough for delicate fish


  • Air may buildup in the unit
  • Filter tends to float and may need to be anchored
  • Requires an air pump and air tubing (not included)
  • The lid can be difficult to remove

Penn-Plax Small World Aquarium Filter

Do you have a starter Betta habitat, perhaps, 5 gallons and under? Then the Penn-Plax Small World Aquarium Filter may be the perfect addition. 

This small (but mighty) filter is designed specifically for those compact, odd-shaped containers and mounts securely to plastic, acrylic, and glass materials with its own suction cups.

The disposable filter contains both carbon and zeolite crystals that remove ammonia, phosphates, nitrates, and nitrites along with those harmful chemicals, toxins, foul odors, and discoloration that can often build up in tiny habitats. The large Bio Sponge captures physical debris (like fish waste and extra food) while allowing the healthy anaerobic bacteria to colonize within it. 

It’s also simple to install – just give it a good rinse and mount on the side of your Betta tank. Do note that this unit requires an air pump and airline tubing to run (sold separately) and may not be whisper quiet. 

Some customers have also complained that the filtration media is “cheap”, so they have replaced it with better sponges and, in some cases, ceramic barrels. 


  • Compact and made specifically for containers 5 gallons and less.
  • Removes harmful toxins and debris
  • Gentle enough for delicate Bettas and shrimp
  • Comes with suction cups for easy mounting
  • Provides the habitat with aeration


  • Filtration media may be considered cheap and inadequate
  • Must replace the media cartridge when it becomes completely soiled
  • Does not come with an air pump and tubing

Lefunpets Sponge Filter

If you are looking for an uncomplicated filter for your Betta tank, then the Lefunpets Sponge Filter may be a great choice for you.

This filter only uses a sponge attached to a weighted base, but the results are incredible. Debris is sucked into the sponge (with the help of an air pump and tubing, not included) where it will begin to grow beneficial bacteria.

The sponge filter is gentle enough to use on delicate Betta, shrimp, and snails as they will not get sucked into the unit. 

Some customers have even modified this model using an airstone for more aeration. In terms of maintenance, the sponge just needs to be rinsed to remove the excess debris. And with four sizes to choose from, it is suitable for most sizes of aquariums.

Do note that some customers had an issue with the filter and recommend running it without the sponge upon installation to ensure the water is being pumped down and therefore creating a vacuum. 


  • Simple to use and install
  • Easy maintenance (just rinse)
  • Comes in 4 sizes
  • Helps create beneficial bacteria
  • Aerates the tank with bubbles
  • Slow-swimmers will not get sucked into the sponge
  • Purifies and clears the water


  • May need to be modified
  • May float until it becomes saturated
  • Needs an air pump and tubing to run (not included)

Weaverbird Mini Sponge Fish Filter

This cute little filter works well in tiny containers you may have thought could not be filtered. It uses an air pump (not included) to pull water into the sponge up the unit and through the top with bubbling action.

It’s the perfect design and solution for tanks under 5 gallons and stays in place with a built-in suction cup. Maintenance is as simple as rinsing the sponge every week or so, and replacing it when it’s worn out.

The Weaverbird Mini Sponge fish filter is quite powerful for its size, but not so much that their slow-moving Betta had an issue with it. You may also have to be careful not to bump the tubing as it could jostle the suction cup loose.


  • Fits 5 gallons and under
  • Great for odd-shaped containers
  • Uses a sponge for easy maintenance
  • Oxygenates the tank
  • Powerful enough to clean, but not so much that it pushes the fish
  • Relatively quiet


  • Does not come with an air pump
  • Suction cup may not be strong enough to hold properly

Newkosea Aquarium Sponge Filter

Your Betta may love this quiet, 5-ribbed filter that uses both mechanical and biofiltration methods to keep his habitat sparkling clear. This simple filter is available in four sizes (up to 40 gallons) with a porous sponge for catching loose debris, while allowing good bacteria to grow on it.

The water outlet can be adjusted for height and the unit can be conveniently placed anywhere in your tank. The Newkosea also comes with an extra sponge, so when one wears out, you still have a backup. The company also recommends soaking the sponge for five minutes in the tank before using it to get it waterlogged. 

It does come with its own suction cup for affixing to the side of the tank; however, customers have complained that it let go over time. And even though it does pump out a lot of water, the design may be a bit flimsy in places. 


  • Quiet
  • 5-ribbed sponge helps clean tanks and grow beneficial bacteria
  • Comes with replacement sponge
  • Adjustable
  • Easy to clean
  • Oxygenates the water
  • Gentle enough for small fish, Betta, and shrimp


  • Does not come with an air pump
  • Some parts may be flimsy
  • Suction cup may not be powerful enough to keep it in place

How Do Filters Work?

Whether you’re new to the aquarium world, or you just never stopped to think about it, you may be asking yourself, how do filters work?

Basically, all filters work the same, regardless of the design. 

  1. Water is pulled into the filter via a pump (this can be at the bottom or top depending on the model)
  2. The water is forced sideways, upwards, or downwards through the filtration media and back out into the tank.

Filtration of the dirty water is achieved through three different methods and media; biological, chemical, and mechanical.

What’s the difference?

Biological – this type of filtration media uses a larger surface to promote and encourage the growth of beneficial bacteria. Biological filtration is found in ceramic barrels, balls, or rings that are placed within the filter. Once established, this bacteria breaks down waste and solids, leaving a fresher, cleaner environment for your fish. 

Chemical – some filters use a carbon insert or carbon/charcoal bits to extract and neutralize harmful toxins from the fish tank. These can be purchased pre-made for the model of your filter, or you can use netted bags and fill them yourself. 

Mechanical – this type of filtration media consists of a sponge. Albeit, simple in nature, the sponge is responsible for capturing debris and fish waste allowing the other processes to work more effectively. The sponge does not change the chemistry of the tank’s water; however, it does allow for beneficial bacteria growth. 

In most fish filters, these three processes work together to create a well-balanced ecosystem.

As the water is pulled into the filter it first has to pass through the mechanical layer (sponge) where all that nasty debris is contained. The next stop is the biological media which is where your good bacteria grow, and once the tank is established, is actually fed by the waste products. Lastly, the chemical layer (carbon or charcoal) further filters out toxins and impurities leaving cleaner water to be pushed back into the aquarium.

Depending on the make and model of your fish filter, the order of the filtration can vary as well as how and when each of these media are cleaned or replaced. 

Why Choose a Betta Fish Filter?

Even though Bettas are sold in tiny cups at pet retailers, that doesn’t mean we should keep them in this cramped (and potentially toxic) environment.  

Yes! Bettas do possess the labyrinth organ that allows them to take oxygen out of the air, but shouldn’t we strive to give them the optimal habitat, one that doesn’t make them gulp at the surface for life-saving H2O?

For this reason, adding a Betta fish filter to a suitable aquarium (even if it is smaller) will provide your aquatic pal with a longer, happier, and healthier lifestyle.

Filters not only aerate the aquarium habitat (which allows your fish to breathe easier), they will also remove toxins such as ammonia, and nitrates that, left unattended, can soon become lethal to your fish.

Some filters will also promote a healthy biofilm within the system by using ceramic rings or balls which help cycle the tank to a healthy atmosphere.  

Plus, using a filter will cut down on the amount of work you will have to do to keep your Betta’s tank clean and safe. 

Remember, small unfiltered containers will need their water changed often, sometimes daily, while filters continue to clean with only a weekly (or bi-monthly) rinsing. In conjunction with weekly partial water changes, your Betta’s tank will be a healthy, nurturing environment. 

Things to Consider When Choosing a Betta Filter

Purchasing a filter for your Betta is not as simple as grabbing the first one you see and putting it into your aquarium.


Betta Biology

Remember that Bettas are delicate fish and are easily pulled into powerful filters. This can damage their flowing fins or lead to more serious issues like stress, hiding, illness, starvation, or even death. 

Choose a filter that is made for slow-moving fish, or modify an existing filter by turning down the flow, adding objects in front of the intake to keep the Betta from being pulled in, or placing netting around the intake.

Tank Size 

The size of your aquarium will greatly affect your choice. For example, you would not want to use the Penn-Plax Small World Filter in a 10 plus gallon aquarium as it would simply be too small, rendering it useless for anything other than some minute aeration. 


How much maintenance do you want to perform with both your aquarium and the filter itself? 

Some filters require the carbon and charcoal components to be replaced at least once a month, while those that contain sponges and ceramic balls only need to be rinsed when dirty and replaced only after they become damaged (3 to 4 years on average). 

Please note that even with a filter in place, we recommend a partial water change at the very least, twice a month. 

Live Plants, Yes or No?

Do you have live plants in your Betta habitat? 

If not, it is recommended that you use a filter with a carbon or charcoal (chemical) medium in your filtration system that will remove the buildup of Carbon Dioxide (CO2) which is created by bacteria and the respiration of the fish. 

The chemical media doesn’t ‘break down the CO2 but rather absorbs it from the water keeping it from re-circulating back into the aquarium. 

Choosing the Best Filter For Your Betta Fish

Please consider all the points we have covered in this post when choosing the best filter for your Betta fish. It’s important to understand and acknowledge that it’s never optimal to house a Betta fish in a small unfiltered habitat, as these require a lot of maintenance and are potentially lethal to your aquatic pal. 

Your Betta will be much happier and more active in a suitable aquarium with even a small filtration system, as opposed to being left to gulp air at the surface and endure poor water conditions.

Choose one of the filtration systems we have reviewed here today, or do some further research to find the best filter for your Betta fish.