8 Reasons Your Betta Has Clamped Fins (& What To Do)

Last Updated on 2023-09-15

Have you noticed that your betta has clamped fins? If so, you’ve found the right article. As you know, clamped fins are definitely a sign of trouble; however, there are a lot of different things that could be causing them! In this article, not only will you find out why your betta’s fins are clamped, but more importantly, what you can do about it!

So keep reading to find out everything you want to know!

What Are Clamped Fins?

Clamped fins are when your betta’s fins are held tightly against their body. While clamped fins are always a sign of a problem, they’re not specific to one problem. In fact, there can be a whole different bunch of reasons that your betta’s fins are clamped.

So before doing anything to treat your betta’s clamped fins, it’s important to find out exactly what’s causing them in the first place!

Why Does Your Betta Have Clamped Fins?

As you can guess, there are many different reasons that your betta can have clamped fins, and being able to diagnose the correct reason is going to be vital for the recovery of your betta. Fortunately, through the process of elimination, you’ll be able to figure out the cause with ease!

It’s also important to remember that in a lot of cases, clamped fins can be caused by stress! So figuring out the cause of stress is vital in helping your betta feel better! So with that in mind, here are the causes of clamped fins in bettas!

Poor Water Quality

One of the most common reasons is poor water quality. If you notice that your bettas fins are clamping, the first thing you should do is check the water parameters, specifically the ammonia, nitrite, nitrates, and pH level!

You should expect to see the following parameters:

  • Ammonia – 0ppm
  • Nitrites – 0ppm
  • Nitrates – 20ppm or below
  • pH – as close to 7 as possible, however, between 6.5 – 7 is also acceptable.

As well as this, you should also consider whether the tank has been cleaned regularly. Even if the water parameters appear good, having a dirty tank could still be stressing your betta out.


The perfect temperature for a betta is 78°F; however, anything between 76-80°F can work as long as it’s consistent. If you notice that the temperature in the tank is too hot or too cold, then this could also be the reason your betta’s fins are clamping.

A Sudden Change In Parameters

As well as poor water quality, a sudden change in any of the water parameters can be extremely stressful for your betta if the tank water heated up a lot or drops in temperature rapidly, for example. As well as temperature, water changes that shift the parameters can also stress your betta too!

Close up of Siamese fighting fish with clamped fins


It’s hard to believe that your betta can get bullied because they’re normally the toughest fish in most aquariums. However, if there are bigger, more aggressive fish in your community tank, or if you’ve put your betta with fin nippers, then it’s entirely possible they’re getting bullied.

If you think this is the case, you should look for other signs of bullying, such as damage to their fins, and if possible, actually seeing the bullying occur.

Other Fish In The Tank

Sometimes even if your betta isn’t being bullied, simply having other fish in the tank can stress them out. If you notice he’s constantly flaring around other tank mates, this is probably the case. Flaring their gills too much weakens their immune system, and over time this can open them up to a whole range of illnesses.

Old Age

Of course, as your betta starts to get older, it’s likely that their immune system is going to weaken as well, which will stress them out. Unfortunately, there’s not much that can be done about this. The best thing to do is try to keep them as comfortable as possible.

Genetic Defects

While it’s somewhat of an anomaly, if you notice that your betta’s fins are always clamped, and they always have been, then it could just be that their fins naturally curl inwards. Once again, there’s not a lot you can do about this.


Lastly, certain diseases, especially the parasitic kind, can cause your betta to clamp their fins. But it’s not just parasites. Any disease or illness is going to stress your betta out and can result in them clamping their fins until they feel better.

clamped fins velvet

How To Treat Clamped Fins In Bettas

Fortunately, behind each cause of clamped fins in bettas, there is also a solution! Here are the things you should do when you notice your betta has clamped fins!

Test The Parameters

The first thing you should do is test the water parameters in the tank. And not only should you do this when your betta has clamped fins, but in the future, you should also do it once every one or two weeks.

This way, you’ll be able to spot if the parameters have changed, and then you’ll be able to figure out if a sudden change in parameters is the cause of your bettas clamped fins.

If you check the tank’s parameters and you notice that the temperature, pH, ammonia, nitrite, or nitrates are off, you’ll need to do everything you can to get them back to normal. This could include adjusting your heater and performing water changes!

API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, White, Single, Multi-colored
  • Contains one (1) API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, including 7 bottles of testing solutions, 1 color card and 4 tubes with cap
  • Helps monitor water quality and prevent invisible water problems that can be harmful to fish and cause fish loss
  • Accurately monitors 5 most vital water parameters levels in freshwater aquariums: pH, high range pH, ammonia, nitrite, nitrate
  • Designed for use in freshwater aquariums only
  • Use for weekly monitoring and when water or fish problems appear

Add More Hiding Places

If your betta is getting stressed out because of other fish in the tank, then a good idea is to add more hiding places in the tank. Plants and caves are the go-to choices, but driftwood and decorations can also work great as well!

On top of providing places for your betta to hide, these ornaments can often break lines of sight, so it’s less likely your betta will even see other fish, which can help reduce their stress as well.

Remove Bullies

Sometimes even with hiding places, some fish may still try to bully or nip your betta. If this is the case, the best thing to do is remove them from the tank and add them to another one. Failing that, you could also buy a 5-gallon tank for your betta and move them to their own space.

Bettas don’t need to be around other fish to be happy. As long as you’re putting enough things in the tank to get them entertained, they’ll be fine.

Try To Keep Feeding Them

If your betta has clamped fins, it’s important to continue feeding them to make sure they keep their strength up. Just dropping one or two pellets at a time for them can make all the difference in their recovery.

And if they’re not eating pellets anymore, try adding some live food like daphnia or brine shrimp to the tank. This way, their hunting instinct may be triggered, and they’ll begin eating again.

Make Sure They Can’t See Their Own Reflection

If your betta can see his own reflection, then it’s possible he’ll begin constantly flaring at it. The most common reason this will happen is when the room you’re keeping your tank in is darker than the tank itself.

When I used to turn my bedroom light off but leave the tank light on, my betta would constantly flare. So make sure you’re doing what you can to stop your betta from seeing their own reflection.

Treat Any Illnesses

If you know that your betta is sick, you should do what you can to treat them. Using medications, changing the water, and moving them to quarantine are all some of the best things you can do.

If you’re not sure whether your betta is sick or not, then check out this article on the most common illnesses and diseases bettas get and what you can do to treat them!

Reduce Noise Around The Tank

Sometimes, noise and commotion around the tank can scare your betta and stress them out as well. It’s not so much the noise that scares them, but the vibrations going through the water. Just like tapping the glass is bad for them, too much noise will produce similar results!

Why Are Your Betta’s Fins Clamped After A Water Change

If you notice that your betta’s fins have clamped after a water change, there could be a few reasons behind it.

  • The water you added has raised or lowered the temperature of the water drastically, and your betta is suffering from temperature shock. If this is the case, you’ll need to slowly start bringing the temperature back to 78°F. If you do it too fast, it could shock their system even more.
  • You forgot to add water conditioner to the water, and now your betta is suffering from the chemicals in tap water. If this is the case, add a water conditioner to your tank as soon as possible.

Why Does Your New Betta Have Clamped Fins?

If your new betta has clamped fins, then it could be simply due to the stress of moving from one tank to another. This is one of the reasons it’s a good idea to leave the tank lights off for a bit when you add a new fish to your tank. It gives them time to destress!

Aside from this, another reason could be because the water parameters they were used to in their old tank are vastly different from the water parameters in their new tank! A good way to help ease their transition into the new tank is to add some API Stress Coat into the water for them.

You should also make sure that you’re floating the bag he comes in on top of the water instead of adding them to the tank straight away. You should also add more and more tank water to the bag they’re in every 5 minutes to help get them used to the new water parameters.

Why Does Your Baby Betta Have Clamped Fins?

If your baby betta has clamped fins, then the causes could be similar to the ones listed above. So make sure you’re checking the water temperature, pH, ammonia, nitrites, and nitrates. As well as this, you can also add an API Stress Coat to the water to reduce the stress your baby is feeling.

Why Is Your Betta Lethargic With Clamped Fins?

One of the main reasons that your betta is lethargic with clamped fins is when the water temperature is too cold. Bettas are cold-blooded, so when the water temperature isn’t hot enough for them, it’s going to slow all their body functions.

As well as this, clamped fins and lethargy can also be caused by protozoan parasites and bacterial infections. Ich is going to be the most likely cause of this; however, it’s also entirely possible that velvet could be behind it as well!

Why Is Your Betta Losing Color With Clamped Fins?

If your betta is loser color, and it’s on their fins, then you should check for fin rot. Often before the fins start to rot away, they’ll start to turn black. pale or lose color.

As well as this, it could also be a symptom of old age. As bettas get older, they tend to lose their color and become paler, and they may also clamp their fins because they’ll be a lot weaker than a young, healthy betta.

Why Do Your Betta Sorority Have Clamped Fins?

If you have a betta sorority, who all have clamped fins, then the most likely cause is a problem in the water. So check the water quality and adjust it accordingly. There’s also a possibility as well that they could all be suffering from the same illness or be in the early stages of one. So once again, you’ll need to treat the illness appropriately.

betta care facebook group


A betta with clamped fins can be worrying. However, in most cases, with the right care, they can recover in no time. In the meantime, you should try to keep your betta as stress-free as possible by reducing noise around the tank, performing water changes, and adding more hiding places for them!

If you liked this article, make sure you check out the rest of the website! Otherwise, have a great day!

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