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Betta Fish Tumor – Symptoms, Cause & Treatment


You’re keen on your betta buddy, and if he all of a sudden develops a white bump on his aspect, does that imply he has cancer

Tumors on fish are typically symptomatic of an underlying well being situation. Nevertheless, in lots of circumstances, a betta fish tumor may be handled efficiently, offered you notice the issue early and take acceptable motion.

So what causes tumors to type on betta fish? And the way do you deal with a lump in your betta?

Learn this information to discover ways to establish and deal with betta fish tumors to save lots of your fishy good friend.

How Probably Is It That A Tumor Will Develop On Your Betta Fish?

Cancerous tumors on betta fish are literally fairly uncommon. In reality, it’s much more seemingly that an harm or a illness will trigger a lump or bump in your pet. So, in the event you spot one thing that appears like a tumor, don’t panic, that is likely to be symptomatic of one thing else solely. 

Mainly, something that manifests as a bump or swelling may be mistaken for a tumor in your betta. So, that features bloating, Swim Bladder illness, and even constipation. Typically, a bacterial an infection can morph into an ulcer or abscess that may seem like a tumor, and small cottony growths attributable to fungus would possibly seem as bumps to the bare eye.

Lastly, a fish tank that has poor water circumstances can produce tumor-like signs, and a nip from an aggressive tank mate may also trigger a lump in your betta’s physique.

How To Know If Your Betta Fish Has A Tumor?  

So, as we established above, there are some things that may be taken for tumors on betta fish.

Easy spots and bumps may become tumors. Tumors can seem beneath the fish’s pores and skin, on the skin of the physique on the scales, and even out of sight inside your betta’s physique on his important organs and different tissues.

If there’s no apparent lump on the skin of your pet’s physique, different signs can point out that he has an inner tumor of some form.

Betta Tumor Or Not?

There are a number of different circumstances which are generally mistaken for tumors on betta fish. 


For those who see a white progress in your betta fish, that’s most definitely an abscess that is likely to be attributable to a bacterial an infection slightly than a cancerous tumor.

Bacterial infections normally emanate from exterior accidents, equivalent to bites from different fish, bumping into tank decorations, or accidents picked up throughout water adjustments and tank cleansing. Accidents may also happen by way of the fish intentionally rubbing in opposition to objects within the tank.

Minor wounds typically heal themselves over time with out remedy. Nevertheless, soiled water can enable micro organism to get into the wound, triggering an infection and establishing an abscess. Abscesses will merely get greater and larger till they rupture, leaving the betta with a big gap in its aspect or ragged fins.

Fungal Infections

Fungal infections usually trigger discoloration of the fish’s scales. In contrast to abscesses, fungal infections normally seem like fluffy cotton. 


Ulcers generally seem as white lumps on the fish’s physique. Usually, these lumps progressively become open, bleeding wounds.

These wounds may cause everlasting disfigurement and scale loss, in addition to offering an entry level for micro organism or fungus.

Typically, most bacterial infections, fungus, and ulcers may be handled efficiently with antibiotics or one other acceptable disease-specific over-the-counter treatment.


Columnaris is a critical situation that usually causes bumps on and across the fish’s head scales that may seem like tumors at first look.


Typically, parasite exercise may cause tissue harm that may manifest as lumps and bumps on the betta’s physique or head.

Swim Bladder Illness

Typically, Swim Bladder Illness could make it seem that the betta fish has a big lump on one aspect of its stomach. 


In an identical method to Swim Bladder Illness, constipation may cause swellings to seem across the fish’s stomach, and the betta can be unable to swim upright or on a good keel.

Often, constipation may be handled by withdrawing meals out of your betta for a few days after which feeding him stay or frozen meaty meals. 

Gill Hyperplasia

Gill hyperplasia may cause harm to the construction of the gills, inflicting them to shrink and grow to be malformed as they slowly heal. That may produce a swelling that seems to be a tumor at first look. In lots of circumstances, that disfigurement is everlasting.

The place Can Tumors Be Positioned?

As mentioned above, lumps and bumps that seem like tumors may be positioned just about anyplace in your fish’s physique, together with:

  • In your betta’s head
  • On the edges of the physique
  • On the fins and tail
  • On the fish’s stomach
  • On the gills

Typically, tumors that develop contained in the fish are cancerous and untreatable. Nevertheless, the lumps and bumps that you just see elsewhere in your pet are normally attributable to different much less sinister causes and aren’t malignant.

What Causes Tumors In Betta Fish?

Identical to individuals, some fish are merely predisposed to growing cancerous tumors. So, basically, there’s nothing you are able to do about it.

That being stated, there are few different issues that may trigger tumors to develop. For instance, permitting carcinogenic substances to get into your tank water, providing your fish a poor weight loss plan, and failing to take care of the setting appropriately. Soiled water can weaken the fish’s immune system, leaving him susceptible to viral infections that would in the end trigger tumors.

How To Deal with A Tumor In A Betta Fish

Sadly, in case your betta fish develops a malignant tumor, there’s probably not a lot you are able to do about it. 

In case your pet develops a tumor, you have to take into consideration his high quality of life. Supplied that the betta is swimming round and is ready to feed, it’s most likely price letting him stay for some time longer. That being stated, in case your fish seems distressed and or disinterested in meals, it’s time to euthanize him.

There are circumstances of individuals efficiently having their betta fish operated on to take away tumors, however that’s the exception slightly than the rule.

When Euthanizing Your Betta Is The Kindest Factor To Do

Typically, the one form plan of action to take when your betta develops a tumor that may’t be cured is to humanely euthanize him.

A fast Google search will deliver up quite a few articles about the easiest way to euthanize your fish. Nevertheless, from private expertise, I like to recommend utilizing a product equivalent to Fin-Quel or one thing comparable you could acquire out of your vet or from good fish shops. These merchandise are literally meant to be used as sedatives, however an overdose will rapidly and peacefully ship your betta on his method to fishy heaven. 

Nevertheless, earlier than you do the ultimate deed, all the time search professional recommendation out of your veterinary surgeon.

Treating Abscesses

For those who’re assured that your betta’s lump is definitely an abscess slightly than a tumor, you may take constructive steps to deal with it.

Take away your pet from the principle aquarium and put him right into a quarantine tank on his personal. The quarantine tank ought to have pristine water in order that when the abscess ruptures, no micro organism will get into the wound and arrange an an infection.

Arrange the quarantine tank with loads of silk crops and a cave or smooth-sided plastic pot during which your pet can take shelter. Bettas can get very careworn once they’re sick and feeling susceptible, so you want to guarantee that your fish has a secure hideout. Silk crops are a more sensible choice than actual ones, as there’s a a lot decrease threat that micro organism will get into the quarantine tank.

Deal with the water with an acceptable over-the-counter aquarium treatment you could get out of your native fish retailer. Comply with the producer’s dosage directions fastidiously and make sure to full the entire course of remedy.

How To Deal with An Ulcer

In case your betta develops an ulcer, that’s treatable! 

Instantly take away your pet from his fundamental tank and put him right into a quarantine setup as described above. Ulcers can become nasty open sores, offering an entry level for micro organism and fungal infections. Whereas your fish is within the quarantine tank, maintain every part scrupulously clear and carry our water adjustments a number of occasions per week.

Following the primary water change, deal with the tank with aquarium salt at a charge of ¼ ounce per gallon of water. That can speed up therapeutic, in addition to appearing as a gentle disinfectant. After every water change, you’ll want so as to add 30% of the amount of aquarium salt that you just added earlier than.

You additionally want to make use of an antibacterial treatment to guard your fish from problems and secondary an infection.  

As soon as the ulcer has fully cleared up, you may return him to his fundamental tank. 

Can You Forestall Tumors In Betta Fish?

Whether or not your betta will get a tumor or not is basically decided by genetics. That being stated, there are some things that you are able to do to guard your fish from growing a tumor.

Purchase Your Betta From A Respected Breeder

If you purchase your betta fish, you almost certainly achieve this from an area fish retailer or on-line breeder. Nevertheless, I like to recommend that you just all the time supply your betta fish from a good breeder. 

Usually, breeders that produce giant numbers of fish for the commerce inbreed their inventory as a result of it’s cheaper than researching genetics and breeding the fish correctly. The results of that inbreeding and lack of genetic screening has led to a complete host of issues, one among which being an elevated likelihood of tumors.

Preserve Your Betta’s Tank Clear!

You must all the time maintain your betta’s tank clear. 

betta fish, siamese fighting fish in aquarium

Soiled water and a poorly maintained filtration system is just about assured to make your betta sick. Bettas are hardy fish however they’re fairly delicate to water circumstances and temperature. For those who don’t sustain together with your tank cleansing, weekly water adjustments, and filter upkeep, your betta’s immune system can be compromised, leaving him susceptible to assault by micro organism and parasites.

To cut back the chance of gill hyperplasia and doable gill tumors, be certain that ammonia and nitrite ranges in your tank are at zero.

Additionally, bettas are labyrinth breathers. To keep away from harm to the labyrinth organ, the ambient temperature within the room the place your betta’s tank is have to be the identical or very near that of the tank water.

Feed Your Betta A Excessive-High quality, Balanced Food regimen

Bettas may be choosy eaters at the perfect of occasions, and feeding a poor-quality weight loss plan is bound to trigger well being points, together with tumors.

Within the wild setting, your betta buddy enjoys a weight loss plan that’s primarily made up of meat with a small amount of plant matter. Your fish wants that stability in his weight loss plan to maintain him wholesome and allow him to struggle off stress-related illnesses. It’s additionally thought that consuming a high-quality, appropriately balanced weight loss plan may also help to cut back the chance of most cancers in individuals, so the identical is probably going on your betta. 

Deal with Different Ailments Promptly

In case your betta fish will get sick, make sure to deal with the issue instantly. The extra time that elapses, the sicker your fish will get, and he may even die.

Typically, the stress of being poorly can go away your betta fish uncovered to the chance of growing a tumor. So, in case your betta develops any type of illness, make sure to deal with him instantly.

Preserve Your Aquarium Free From Carcinogens

There are some chemical substances which are recognized to trigger most cancers in pet fish. So, earlier than you add something to your fish tank, make sure to verify that the substance is secure and doesn’t include something carcinogenic.

In Conclusion

I hope you discovered our information to tumors in betta fish useful. For those who did, please bear in mind to share the article with different betta fanatics.

Fortunately, cancerous tumors in betta fish are fairly uncommon. Sadly, in case your fishy good friend does get a malignant tumor, it’s unlikely that it is possible for you to to save lots of him. Nevertheless, your betta would possibly develop lumps and bumps which are attributable to different illnesses and unintentional trauma. That,, lots of that are completely curable and preventable.

Did your betta fish get a tumor? How did you deal with it, and the way is your betta buddy doing now?


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