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Betta Fish Tumor: Should I Be Worried?

betta fish tumor

Betta fish are exposed to a lot of risks for any duration of time. If tank parameters are not maintained optimally, your betta fish is bound to lose its colors out of stress and infections. Your Betta can get many diseases, and the most worrisome for the betta owners is a betta fish tumor.

Betta fish tumors are recognizable by lumps and bumps on the body or head of your beautiful betta fish. These lumps can be internal as well as external, which will be visible. Nevertheless, out of the many diseases your Betta can catch, it is unlikely for your Betta to get hold of this disease. Betta fish tumor is extremely rare in betta fish. If you are noticing lumps and bumps in your betta fish, it might be because of other diseases, which are more likely to happen, like swim bladder disease, white spot disease, or any other fungal or bacterial infection. If you worry about the betta fish tumor, we have dedicated this post to the topic.

What Is Betta Fish Tumor?

What Is Betta Fish Tumor?

A tumor on a Betta fish is typically an indication of unstated serious health abnormalities that you being the betta fish owner, must deal with as soon as possible. Tumors or cancer cells are a prevalent origin of Betta fish tumors. Some bettas, like some humans, are genetically subject to acquiring malignant tumors.

There isn’t much you can do to prevent it, and it is practically the fate of your Betta to develop a betta fish tumor. This is the most typical reason for this ailment.

However, there are also some other reasons why a healthy betta develops tumors. Poor nutrition, contaminated water, and infectious diseases are just a few of them. Allowing carcinogens into your aquarium, offering them crappy food, and allowing different pathogens in its tank caused by poor water quality can all increase the likelihood of a tumor developing.

A tumor on a Betta fish can be little or large, and it can appear anywhere on the Betta, such as on the tail, lateral plates, the forehead, or internally as brain cancer. Minor tumors may have little impact on your pet, but greater tumors might make swimming harder for your Betta fish.

Is It A Betta Fish Tumor?

If you suspect your Betta has a tumor, keep in mind that it might be anything else entirely. Ulcers and abscesses, for example, might resemble tumors. A tumor can be masses produced by a swim bladder infection, bowel problems, or water retention too.


The clear-cut indication of an abscess is lumpy white extensions from your betta fish’s body. Your fish’s white swelling is most probably an abscess produced by a bacterial infection. A pus-filled abscess is the most common type of abscess. It may even explode throughout a period. Pathogenic bacteria are the source of abscesses. Your Betta might be injured. In most cases, such injuries heal on their own.

However, if the tank water isn’t kept clean, bacteria might get into the injury and cause an infection. Scale discoloration is mainly caused by fungal diseases. External tumor morphologies induced by bacterial infections are hard, whereas fungal infection extensions are generally spongy.


Ulcers betta

An ulcer is yet an additional white tumor-like condition. These commence as a bump with red discoloration encircling it and progress into exposed injuries. An ulcer is frequently caused by a deterioration in your pet’s immunity. Ulcer-affected fish are generally sluggish and malnourished to the extent that they cease feeding entirely.

Bacterial infections are the most common incidence of fish ulcers. Many bacteria are naturally found in a clean aquarium and pose no threat to the fish. However, once the Betta gets stressed due to poor water quality or harsh tank conditions, they are prone to bacteria, which can develop ulcers.


Overfeeding a betta is the most common problem among betta fish. Overfeeding your Betta might cause bloating in your Betta, which might eventually lead up to swim bladder disease. This bloating might seem like internal tumors in your Betta. This will affect your Betta’s swimming patterns. The best way to deal with it is to stop feeding Betta and prevent overfeeding in the future.


Columnaris is a microbial condition that can damage all of your aquarium’s fish. Cotton wool, saddleback illness, and guppy disease are some of the names given to it. Livebearers are more likely to have it. Tumor-like lumps surrounding and on the forehead scales are a possible detrimental effect of Columnaris. If you notice a betta fish tumor on your nose, it is probable that your Betta is suffering from columnaris.


If your Betta has dropsy, you’ll note that it’s swollen, has a bent backbone, and, in the later phases, slightly curved scaling. Regrettably, if your Betta has dropsy, you will have a difficult time preserving it. Dropsy looks like a betta fish tumor on the stomach. In truth, a betta can live with a tumor for a considerable time, but if dropsy becomes too bad, they’ll perish in a matter of nights.

Betta Fish Tumor: Symptoms

Betta Fish Tumor: Symptoms

A Swell or a bump is the only definite sign of a Betta fish tumor. Internal development, such as brain tumors, will be more difficult to identify in the initial days than exterior tumors. Internal tumors frequently become evident as the body expands due to edema. Lack of desire to eat, being drowsy, difficulties with stability, or swimming are all signs that could suggest a betta fish tumor.

Betta Fish Tumor: Causes

As said earlier, the betta fish tumor is due to the development of cancer cells within your fish. There is no such thing that you do that causes it, but it develops naturally. Maybe poor water conditions or diet could worsen it or trigger it, but it is majorly naturally developed.

Betta Fish Tumor: Treatments

If, in fact, it is a betta fish tumor, there are no such treatments options available to treat a betta fish tumor, sadly. Tumor removal surgeries are available, but the success rate of these treatments is nil. The best way to treat Betta fish tumor is to prevent it with good tank conditions, water quality, and dietary needs.

Betta Fish Tumor Vs. Bacterial Ulcer:

BasisFish TumorBacterial Ulcer
Causes It is due to the cancerous cell developed in your BettaAn ulcer is caused when your Betta’s immunity weakens due to poor water quality
Treatment There is no such treatment available for fish tumors. A bacterial ulcer is treatable, through medication.
External featuresBumps anywhere on the body, sometimes white in color. Ulcer results in lumps on the body, which is white too but with reddish edges
InfectionA tumor is not an infectionAn ulcer is a bacterial infection triggered by poor tank conditions.

FAQs on Betta Fish Tumor

How to prevent a betta fish tumor?

By having the tank conditions that are the best for betta fish, you can prevent betta fish tumors. Make sure you give your betta fish the best tank, with an appropriate diet and proper filtration as a measure of prevention.

What to do if the fish has a tumor?

We recommend taking your fish to the doctor immediately if you suspect that your fish has a tumor. He or she will surgically remove the external betta fish tumor.

How long can a Betta fish live with a tumor?

A betta fish can live not more than a few months with a tumor. Make sure you provide your fish with all the right tank parameters during their tumor days.

How to treat a gill tumor in betta fish?

If your Betta has a lump on the gill, it can be gill hyperplasia which is caused by injury or bacterial infection in the gills of your Betta. In most cases, this lump goes back normally with proper water quality and chemical treatment, but in some cases, it might not go back.

Final Thoughts:

A betta fish tumor is an extremely rare condition in your Betta. It is most likely that your Betta has developed a certain infection, which may be bacterial, fungal, or parasitic. Ensure proper filtration and cleaning of tank water if you want to prevent these infections and give your Betta a healthy life.