If you’re looking for a new filter, then you may be curious what the best filter for 5 gallon betta tanks is! Because finding the right filter is one of the most important things you can do. The right filter is going to keep the water in your tank clean, whereas the wrong filter may end up turning it inhospitable.
In this article, not only are you going to learn what the best filter for 5 gallon betta is, but you’re also going to learn how to choose the right one! So keep reading to find out more.
In A Hurry?
If you don’t have time to read the whole article then here’s a list of the best filters you can choose for your betta’s tank.
HOB Filters
- Penn Plax Cascade Hang-on Aquarium Filter With Quad Filtration System
- AquaClear 20 Fish Tank Filter – 110V
- Marina S10 Power Filter
Internal Filters
Canister Filters
Undergravel Filters
Best Type Of Filter For A 5 Gallon Tank
Generally speaking, HOB (hang on back filters) are the best filter you can have in a 5 gallon tank. They allow more space in your tank while not being as expensive as canister filters. (however, they’re also not as effective as canister filters.)
But you should always pick a filter depending on your own specific needs. Here’s a little more information about each filter.
HOB Filters
HOB filters use a pump to push water through media filters and then back into the tank. They are great for smaller tanks because they’re not going to take up any room.
One problem with a lot of HOB filters is the fact they often don’t have adjustable flow. However, this can be fixed.
Canister Filters
One great thing about canister filters is they normally have more space in them. Meaning you can add more filter media. In smaller tanks ammonia, nitrites and nitrates can build up a lot quicker, so access to more filter media will allow you to keep the tank cleaner AND for longer.
However, the downsides are, they’re normally more expensive and in most cases, you’ll have to place them below your tank.
Undergravel Filter
While undergravel filters aren’t seen as often it doesn’t mean you shouldn’t use them. Instead of using filter media, these filters use the gravel they’re placed underneath as a filter.
The gravel will act as biological and mechanical filtration, and will only require vacuuming every once in a while. Which is a lot easier than taking a filter apart and cleaning it.
However, the downsides of undergravel filters are the fact you can only really add them when you’re setting your tank up. And that there’s no chemical filtration (which you’ll need if you have to medicate your tank).
Internal Filters
Internal filters are another common filter you see in a lot of tanks. They use a tube which is normally situated outside of the tank to suck water through a sponge trapping debris and housing beneficial bacteria.
The only downsides of internal filters are that you’ll have to clean them regularly and they’ll take up space in your tank.
(Want to know what the best tank for a betta fish is?)

What To Look For In A Filter For Bettas
As well as knowing the different types of filter, there are also certain things that make a filter great for bettas. So you should always look for a filter that has the following.
Adjustable Flow Rate/Low Flow Rate
Bettas don’t like a lot of current in the tank because they’re going to find it hard to swim in. When looking for a filter you should use one that has a low flow rate or one you can adjust.
However, if it can’t be adjusted manually, there are things you can do to adjust it yourself. Such as adding sponge to the intake tube.
3 Stages Of Filtration
Most filters come with 3 stages of filtration as standard. Mechanical filtration for debris, chemical filtration for chemicals and biological filtration for bacteria. While chemical filtration can be swapped out, you still want to be able to house at least 3 forms of media.
Low Noise Level
The last thing you want is a loud filter. It can turn your fish tank from something peaceful to a constant annoyance. While a lot of smaller filters are quiet anyway, some of them can become irritating fairly quickly.
The Right Size
And lastly, you don’t want a filter that’s too big or too small. If the filters too big then it could cause a powerful current that’s far too strong. And if it’s too small then it’s not going to adequately clean your tank.
The Best Filter For 5 Gallon Betta Tanks
All of the filters below are going to do an excellent job at keeping your tank clean and your betta happy. However, if you’re wondering what one just excels over the rest then it has to be the AquaClear 20 Fish Tank Filter.
AquaClear 20 Fish Tank Filter
The Aquaclear Fish Tank filter is a great little filter that’s reasonably priced but is still fantastic at keeping your tank clean. When you look into your tank with this filter, you’ll notice the water is crystal clear and it feels like you’re seeing your betta in HD!
It comes with mechanical, biological and chemical filtration, with each part working to make sure the tank is safe for your beta so you don’t have to worry.
Not only does it have all 3 stages of filtration, but it also has refiltration which means a greater amount of water will come into contact with the filter media, making your tank EVEN cleaner.
Another added benefit is the fact it fits SEVEN TIMES the filtration media as other similar sized filters!
The cutting edge refiltration design is what lets you adjust the flow of this filter as well. In fact, you can slow the flow by 50%, which is exactly what your betta needs. And the slower the flow, the more immaculate the water becomes
And because it’s a HOB filter you’re not going to have to worry about it cluttering your tank and taking up precious space for your betta.
Is It Beginner Friendly?
Because this filter hangs on the back of your tank it’s extremely easy to use. Setting it up takes about 10 minutes, and when you need to change your media you simply take the top off and pull it out. You just need to make sure you prime it before turning it on. (Just fill it up with water beforehand.)
Best Features
- Adjustable flow & refiltration.
- SEVEN TIMES the filtration media of other filters.
- 2-year warranty.
Improvements
- While it’s still an inexpensive filter, it does cost a tiny bit more than other filters for 5-gallon tanks.
Best Hob Filters For 5 Gallon Tanks
While the Aquaclear 20 Fish Tank Filter, is the best allrounder, you may be thinking it doesn’t quite fit your needs. Here are the other best hob filters you can use on a 5 gallon tank!
And if you don’t want a hob filter scroll down for the best undergravel, canister, and internal filters.
Penn Plax Cascade Hang-on Aquarium Filter With Quad Filtration System
While it may not be as good as the Aquaclear 20, it still has a lot of great features. The Penn Plax Cascade hang-on filter, is great for filtering tanks up to 7 gallons.
It comes with a biological filter media, as well as a mechanical and chemical filter cartridge that you’ll need to replace every 6 – 12 weeks (depending on how dirty the tank is).
What’s great about the biological media is that it’s wet/dry. Meaning it’s constantly being exposed to air, increasing the rate at which beneficial bacteria will grow on it.
However, while it comes with its own unique filter media, you don’t have to use it. It’s easy to add your own filter media if you choose to!
And of course, you can also adjust the flow rate of this filter. You won’t have to worry about watching your betta being pushed around the tank by the water! In fact, you can turn the water into his own mini paradise.
One big problem with the Penn Plax is its flow rate. At 20GPH (gallons per hour) it’s not bad, but it’s nothing stand out. The slower the flow rate, the less the tank can be filtered and cleaned.
Is It Beginner Friendly?
If you’re not sure how to set up HOB filters there’s a handy guide on youtube by Penn Plax themselves. And not only is setting up it easy. The maintenance is easy as well! Simply pop the top off remove the filter media, clean them and pop them back in!
Best Features
- Wet/Dry biological filtration
- Adjustable flow rate.
- Enough room to use your own filter media.
Improvements
- A flow rate of 25-30GPH would greatly improve this filter.
- The filter cartridges that are meant to be used with this filter aren’t for everyone. You may be better off buying your own.
- The color is a little unsightly and can distract you from the beauty of your tank.
Marina S10 Power Filter
While the Marina Power Filter is suitable for tanks up to 10 gallons, that doesn’t mean it won’t fit great in your 5 gallon tank. In fact, on the surface, this looks like the best filter you can buy, but unfortunately, it does have one huge flaw.
Once again, it’s another filter that has an adjustable flow. So even though it’s for 10-gallon tanks, this feature is going to make it perfectly suitable for a 5-gallon betta tank!
On top of this, it also has a strainer sponge on the end of the intake tube. If you’re like me you often worry about the intake ruining your betta’s fins or sucking up small tank mates. There’s nothing more harrowing. However, the intake strainer is going to prevent this from happening!
Instead of inserting filter media, you’ll have to insert marina’s own filter cartridges. While the filter cartridges are good, they do lack customization. With that being said, to a certain level, you are able to add the filter media you want to this filter.
The biggest problem with this filter is the motor. Instead of being inside the filter casing like most filters, it’s on the intake tube. It looks bulky and takes up a lot of space. It takes away from the point of HOB filters which is to save space in your tank.
And lastly, the Marineland S10 Power Filter is also self-priming. So you don’t need to fill it up before turning it on. While this may not seem like a big deal, it does save a little bit of time.
Is It Beginner Friendly?
Just like most HOB filters, the Marina S10 is incredibly beginner friendly. However, to get the most out of it you should add your own media which can be confusing for new betta owners.
If you’re worried about learning to set it up then don’t be! there are lots of tutorials on youtube that show you how.
Best Features
- Self-priming.
- Adjustable flow.
- Strainer Sponge
Improvements
- The motor takes up so much space in your tank, it would be nice if there was somewhere else for it.
- The media that you’re supposed to use in this filter is expensive.
Best Internal Filters For 5 Gallon Tanks
If you don’t want a HOB filter, then you can also add internal filters to your tank. While they’re normally better suited to larger tanks, that doesn’t mean you can’t still add them to your 5 gallon. Here are the best internal filters.
Aqueon Quietflow Internal Power Filter
The Aqueon Quietflow Internal Power Filter is a reasonably priced filter. However, that doesn’t stop it from being a fantastic filter for any 5 gallon tank.
It comes in standard black coloring which allows it to blend into the background of most tanks. However, like all internal filters, it’s still noticeable.
While it’s meant for a 10 gallon tank, it does have an adjustable flow, so you can turn the flow down and it will produce a slow current your betta won’t have any trouble swimming through.
Not only do you have the option of choosing whether you want to dramatically drop the flow rate or not, but you can also choose what direction you want the flow to come from. This is thanks to the extendable and rotational outflow tube.
And as the name suggests, this filter is an extremely quiet filter. If you’re looking for a silent filter for your room, then this is a great choice (noise wise).
The filtration that comes with this filter is okay, but for the best results, you’re going to want to add your own filter media. Not only will this be more effective, but it will also save you money. But mechanical, biological and chemical media come as standard.
And the last great feature of this filter is the limited warranty it comes with.
Is It Beginner Friendly?
While setting up is easy, maintenance is a lot more annoying. You’re going to have to remove the whole filter, and it can often be hard to get into the hard to reach spots. While it is beginner friendly, it’s going to take more time than a lot of other filters to maintain.
Best Features
- Extremely adjustable flow. Not only can you control the rate, but also where it comes from.
- A quiet filter, just like the name suggests.
What Can Be Improved?
- Changing the filter media can be a bit strenuous and you’re going to have to completely remove the filter to do it.
- The filter cartridges that come with it aren’t the best, and you’re better off adding your own.
- It’s not pleasing to look at in your tank.
Tetra Whisper In-Tank Filter with BioScrubber
The tetra whisper in-tank filter is another choice you may consider. However, while it’s made for 10 gallon tanks, it can work in 5 gallon. One thing to note is that it’s one of the largest filters on this list. And if you do add it to your tank it’s going to take up a lot of space.
However, if you can look past its large size, one thing is for certain. It certainly is whisper quiet. Because it’s placed in the tank, a lot of the noise that’s caused by the impeller is muted by the water.
The Tetra Whisper also comes with 3 stage filtration. First, of course, is mechanical filtration. It’s a dense mesh that catches any large pieces of debris before the water is filtered through the activated carbon filter. And lastly, once the water is as clean as possible it then moves through the biological filtration, where any ammonia and nitrates are removed.
One problem is that there’s not a lot of room to add your own media. But the filter does what it’s supposed to do, and you won’t have to worry about your betta having to live in dirty water.
However, one thing that you should be aware of is that even though there are a lot of problems, this is a cheap filter. If you’re on a budget then it may be the one for you. However, you’re definitely better off buying some of the other filters on this list.
Is It Beginner Friendly?
The filter is incredibly easy to set up and install in your tank. You just have to stick the sucker to the tank and it will stay in place. Changing the media inside is also easy except you’ll need to remove the filter to do so.
It also comes with instructions showing you exactly what you need to do, so you shouldn’t have a problem installing it.
Best Features
- As the name suggests this filter is nice and quiet
- The filtration will get the job done, and keep your tank clean.
- It’s cheap.
Improvements
- The size of the filter is too large, it would be nicer if they reduced the size.
- Not a lot of versatility when it comes to changing the media.
Best Canister Filters For 5 Gallon Tanks
While it’s hard to find canister filters for such small tanks, it doesn’t mean they’re non-existent. Here is the best canister filter for 5 gallon tanks
Zoo Med Nano 10 External Canister Filter
If you’ve got the money or you’re looking to upgrade to a bigger tank soon, then this is DEFINITELY the filter you’re going to want. The Zoo Med Nano 10 has a whole range of great features and very few drawbacks.
The Zoo Med is made for tanks that are 10 gallons in size or smaller, and it really shows with how much media you can add to the inside. If you use this filter your tank is going to be absolutely spotless, and you’ll be able to modify what you’re using to your heart’s content.
And of course, it doesn’t take away from the space in your tank. Because it’s a canister filter, you just have to place it by the side of your tank, and you’ll only have to insert two non-intrusive tubes into your tank. One of these tubes is going to be the intake, and the other will be the output.
A great feature of the output of this filter has is that there are two different output methods. You can either choose a nozzle or a spray bar. If you’re worried the current is going to be too strong, then you should use the spray bar which will reduce the water flow rate, whilst improving surface agitation.
However, if you don’t want to use the spray bar, you can also angle the output nozzle against one side of the tank to slow the flow.
Because it’s a canister filter, and it’s so efficient it also means you’re not going to have to clean your tank as often. In fact, in a 5-gallon tank, you can leave it for about 2 weeks without having to clean it!
And when it comes to the filter itself, cleaning is also incredibly simple. You just have to take the top off pull out the media, give them a rinse in water, before adding them back. Every once in a while you’ll also need to clean the impeller, but it’s incredibly easy to get too.
As a last little benefit, it also has suction cups on the underside which drastically reduce the noise of this filter.
Is It Beginner Friendly?
As far as being beginner friendly, it’s initially a little bit more difficult to set up, but once that’s done, it’s going to be easy to look after. Fortunately, you can look online for tutorials on how to hook it up properly. As well as this, it will also come with handy instructions!
One thing beginners might be apprehensive about is priming the filter, but it’s incredibly easy once you know what you’re doing!
Best Features
- Doesn’t take up space in the tank itself.
- Plenty of room for various filter media.
- Extremely quiet.
- Comes with a spray bar or output nozzle.
- Your tank won’t require maintenance as often.
- Incredibly easy to set up and clean
- The spray bar aerates your tank as well.
Improvements
- Better flow adjustment, while a spray bars good, adjusting the flow from the filter would be better.
- It would be nice if it was cheaper, however, it is a top quality filter.
Best Under gravel Filters For 5 Gallon Tanks
If you haven’t set up your tank yet then it may be worth your time using an under gravel filter. They generally require little maintenance once set up, because it’s the gravel itself that’s going to act as the filter media. So you’ll only need to vacuum it!
Here are the best under gravel filters.
Penn Plax Cfu55Ug Fltr
One of the worst things about this filter has to be its name. Unfortunately, that’s not a typo, it’s just how it’s spelled. However, it is a great under gravel filter.
You have to realize that when you’re adding an under gravel filter, it’s not the filter so much that’s important, however, but the gravel and pump you use. Saying that though the Penn Plax Cfu55Ug Fltr is very sturdy and if you add it to your tank it’s going to do a great job.
The best feature of this filter is the fact it’s practically silent. In fact, it’s one of the quietest filters on this list. Because it uses a smaller pump to move water, and it’s only going through the gravel, it ends up being quieter than a lot of other methods.
As well as that it’s also extremely easy to maintain. All you have to do is vacuum the gravel once in a while which is acting as the mechanical filter.
And lastly, the filter itself is inexpensive. Of course, you’ll also have to buy the gravel, however, you’d need to get that anyway, and asides from that you’ll only need an air pump to pump the water!
Is It Beginner Friendly?
While under gravel filters seem daunting to beginners they’re easy to set up, and once they’re set up maintenance in minimal. However, if you try to add an under gravel filter to an established tank then it will be hard for beginners and veterans alike.
Best Features
- This filter definitely isn’t going to cost you much money.
- It’s easy to maintain because all you have to do is gravel the vacuum.
- It doesn’t take up much room in your tank, because most of the filter is under your gravel.
- Also, it’s really quiet.
Improvements
- Unfortunately, like all forms of filter, there’s only mechanical and biological filtration.
- You’ll need to have a gravel floor and buy an air pump.
Lee’s 5-1/2 Original Under Gravel Filter
Last on the list is Lee’s 5-1/2 Original Undergravel Filter. It’s another undergravel filter that fits perfectly in most 5 gallon tanks.
Once again, it’s another filter that you’re barely going to notice since it’s undergravel, and it’s made of really sturdy plastic.
You shouldn’t have to clean the filter too often if you look after your tank. Normally you’ll only have to vacuum the gravel every week.
One thing to note is that for best results you should add more gravel than usual.
However, the only downside is that the tubes could be more flexible.
Is It Beginner Friendly?
If you’ve never set up an undergravel tank before the instructions aren’t the clearest. However, there are lots of tutorials you can watch on youtube. Apart from that, once you’ve got it set up it’s extremely easy to maintain.
Best Features
- Sturdy and long-lasting.
- Easy to maintain once it’s setup.
- Barely noticeable in your tank.
Improvements
- Instructions could be clearer and more helpful.
- Intake and output tubes could be more flexible.
In Conclusion
As you can see it’s hard to pick the best 5-gallon filter for betta tanks! However, the best all-rounder has to be the Aquaclear 20. But if you have the cash to splash out and you plan on upgrading to a slightly bigger tank then I’d definitely recommend the Zoo Med Nano 10.
Betta fish care can be challenging if you have no idea where to start. Click here to read a complete Betta fish care guide!