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5 Reasons Behind Betta Fins Curling and Its Prevention

Betta Fins Curling

Beautiful and vibrant colored fins characterize betta fins. But sometimes, you may notice betta fins curling and clamping. Some may suggest fin rot, but this is not always the case. Curling of betta fins can be caused for various reasons, and the mode of treatment varies accordingly.

The most common causes of betta fin curling are old age and genetic abnormalities. This might be due to damage or insufficient tank factors such as water pH, ammonia, nitrates, and water quality. These circumstances, as well as illnesses, can cause the betta’s fins to get clamped.

Betta Fins Curling: Causes & Prevention

Some people instantly believe fin rot is the reason behind betta fish curling. However, this is an uncommon occurrence. Curled fins, for starters, are typically a sign of a problem. They are not an issue in and of themselves. Many aquarists will claim that their fish have curled fins but are otherwise healthy and happy.

This is not always the case. However, it is critical to recognize that curled fins are a symptom since this forces you to look for the source of the problem. Curled fins in bettas can be caused by a variety of factors.



Bettas can live for 2-4 years on average, but with appropriate care, they can live for up to 10 years. However, no matter how well you care for them, all bettas ultimately wear out. The curling of fins at their ends is one of the signs of aging. Betta fins will tear and twist as they age.


There is nothing you can do to halt or reverse this process. Curling fins are a regular phenomenon in bettas that have been persistent for a long time. Old bettas also have other characteristics like fading colors, drowsiness, and white patches.



A genetic abnormality causes curling in certain betta fish. A genetic aberration in bettas, like the aging factor, cannot be corrected. If your bettas had curled fins when they were born, the fry they produced would have the same problem. In such instances, your only choice is to get rid of the problematic betta fish.


You should avoid breeding that specific betta fish if you believe this is the case. The following generation will very certainly face the same problem. Also, young bettas who have been swimming with curled relatives should be avoided. In the future, they will be more prone to develop symptoms.

Water Quality


Water hardness is the amount of minerals present in the water. The pH of water is closely related to its hardness. The higher the level of dissolved minerals and the higher the pH, the more complex the water is and vise versa.
Every fish species has a maximum hardness it can withstand. Bettas, for example, flourish in water with a hardness of 5 to 20 dH. The fins of your betta fish might curl if the water is too harsh. Fortunately, if this is the case, the problem can be resolved. You can use water softeners to reduce the water hardness.


Betta fins curling as a result of water hardness are not always a reason for concern. The betta is not in any discomfort, and the only thing that matters here is appearance. This is important to remember since water hardness is a complicated problem.

You risk drastically changing the pH of your tank while attempting to repair it, making the problem in your tank much worse. If you have any doubts about your ability to adjust the hardness without changing the pH, you should ignore this problem. That is especially true if you are not bothered by your bettas’ curled fins.



Bettas tend to be aggressive. The males, in particular, are very territorial. As a result, betta injuries are nothing new. Fins are an easy target. When a betta’s fins are injured, there is no assurance that they will mend in the same way they were before. If your fish is in good health and the water is suitable, any curled fins you notice are likely the result of injury.


Some injuries, however, will heal on their own. As a result, the mode of treatment in this situation is primarily preventative. Make sure you have ruled out any other possible causes for the bruise. If your betta and another fish share a tank, try separating them. If your tank has any pointy objects or decorations, you should remove those as well.



In fish, stress can cause a range of symptoms, including betta fins curling. Small tanks are one of the most prevalent causes of stress in betta fish. You could also have a look at the bettas available at your local pet store. Because they are housed in such small enclosures, many of them have curled fins.


You should probably upgrade your betta tank if it is less than five gallons. Consider the betta diet if the tank size is not the issue. Make sure your bettas are getting lots of protein-rich food. Larger, more aggressive fish should be kept away from them, and plants that provide hiding places should be added.

FAQs Related to Betta Fins Curling Problem

What are clamped fins?

Clamped fins are seen in fish that keep their fins close to their bodies most of the time rather than opening them in the typical fashion. Fins may be frayed, torn, or damaged, or they may be in good condition but closed.

Why are my fish’s betta fins curling?

The most common causes of betta fin curling are old age and genetic abnormalities. This might be due to damage or insufficient water factors such as pH, ammonia, nitrates, and water hardness.

How is betta fins curling different from fin rot?

Make careful you do not confuse betta fins curling with fin rot, which requires a different treatment. In case of fin rot, the fins get damaged and discolored (black, white, and brown) due to the illness.

Final Thoughts

Environmental variables such as stress and poor water conditions can cause betta fins curling. To fix the problem, make sure all parameters like pH, ammonia, nitrates, etc., are within the acceptable range. You should also get rid of any sources of stress, like small tank size or incompatible tank mate.