Betta Fish Diseases: Cause, Symptoms, Prevention & Treatment In 2023 ( With Pictures)

20 Betta Fish Diseases: Cause, Symptoms, Prevention & Treatment In 2023 ( With Pictures)

Bettas are very tough fish that can live in conditions that would kill most other fish in a short amount of time. Betta fish get sick easily, but most of the time they can get better. When we feed the bettas every day, we should make it a habit to watch them. Over time, we will be able to tell when a betta fish is sick. As a fan of betta fish, you should know about their diseases and be ready to treat one if it gets sick.

  1. Introduction
  2. Symptoms of a Sick Betta Fish
  3. 20 Most Common Diseases on Betta Fish: Cause, Symptoms, Prevention, and Treatment
  4. Fin and tail rot
  5. Columnaris
  6. Hemorrhagic
  7. Dropsy
  8. Popeye
  9. Cloudy Eyes
  10. Furunculosis
  11. Velvet
  12. Ich, Ick, or “White Spot Disease”
  13. Anchor Worms
  14. Hole in the Head
  15. Swim Bladder Disorder or Flipover
  16. Betta Tumors
  17. Mycobacteria
  18. Constipation
  19. Ammonia Poisoning
  20. Slime Disease
  21. Fish Lice
  22. Gill Flukes
  23. Red Streaks
  24. Tips for Treating Diseases in Sick Betta Fish
  25. Conclusion


Betta fish suffer from a variety of health issues, but the good news for keepers is that these issues can be avoided and treated. If the infections occur in the aquarium, they are easily identified and effectively treated.

This article talks about all of the most common diseases and illnesses that affect betta fish in 2023, as well as how to avoid, diagnose, treat, and cure them. If you have a Siamese fighting fish at home, keep reading to find out how to keep your aquatic pet healthy.

Betta fish illnesses and diseases are classified as fungal, parasitic, or bacterial. The majority of fungal infections are the result of pre-existing medical conditions. Parasitic illnesses are the most contagious, and new fish can introduce them into the aquarium. The most common causes of bacterial illnesses are poor water quality and improper fish handling techniques.

Symptoms of a Sick Betta Fish

While it’s important to note that there are a wide variety of symptoms that may not be outwardly visible when something is going on with your betta, there are some very noticeable ways to tell that something is wrong. These visible signs include:

Betta Fish Losing Color

In most cases, illness is detected in your fish when its color pales or lightens.

The color-producing cells in your Betta’s body won’t have the energy to properly show their fullest, brightest sheen and will appear duller than normal.

The betta’s head may also look different from the rest of its body, which is another sign that something is wrong.

Damaged Fins

While Betta fish are known to be aggressive and can often come with preexisting fin and tail damage, seeing clamped fins, tail rot, or receding fin edges is a sign of something more concerning.

Mild fin rot can quickly progress to your fish losing the ability to swim completely as bacteria on the betta’s fin and tail wear away the tissues over time.

Change in Appetite

Another reason that it is important to keep tabs on the regular comings and goings of your betta fish is so that you can notice things like a change in appetite.

If you know that your fish is typically a slow eater, it may not seem unusual for it to take some time with its food.

On the other hand, if you know that your fish is a regular eater and you notice your betta fish not eating or ignoring the food, you may have a sick betta fish on your hands.


Most Betta fish diseases will leave your fish tired and struggling to remain active.

You may notice that your betta is sitting at the top of the betta tank or laying along the bottom of the tank.

Sometimes we think a sick fish is just sleeping, but if your fish stays still for more than a few hours after it would normally be awake, you may start to worry that it has a bacterial infection or is sick.

Gasping for air

Gasping for air is a symptom of many common betta fish diseases and fungal infections of the gills. It indicates that your fish is not getting adequate oxygen.

There may be a fungal infection around the gills, a parasite like Dactylogyrus that is stopping them from working properly, or the conditions in the tank as a whole may have reached a point where there isn’t enough dissolved oxygen for your fish to breathe.

Rubbing Fins on the Fish Tank Itself

As a result of fungal infections that cause fin rot or tail rot, your fish will attempt to rub off the afflicting agents onto the tank.

It may run along the substrate of the betta tank as well, but either way, this is a sign that something is not right with the fish.


Seeing a Betta fish with a swollen stomach is a definite cause for concern.

This could be a sign of constipation, a fungal infection, or a bacterial infection that is causing gasses or undigested food to accumulate within the fish.

This bloated look is not only uncomfortable; it can mean that your fish is in danger of potential death.

Enlarged Eyes

Swollen eyes are a sign of infection and suggest that something has gotten into the tissues around the eyes or head, or even a mouth fungus (fish fungus) may be suspected.

Your fish may be in danger of losing one or both eyes, and precautions need to be taken to prevent further spread.

  • Puss: As with human wounds, puss is a sign that the betta fish is fighting off an infection. Puss itself indicates that the white blood cells within the fish are doing their best to fight off some form of outside intrusion and that your fish may likely need medical care.
  • Erratic Swimming: In contrast to lethargy, swimming in irregular ways can be a sign of distress or illness. Seeing a fish swim sideways, upside down, rapidly, or at the surface can all indicate that something is going on with your fish.

20 Most Common Diseases on Betta Fish: Cause, Symptoms, Prevention, and Treatment

Fin and tail rot

Fin and tail rot on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is fin and tail rot?

One of the most prevalent and easily treatable ailments affecting aquarium fish is fin and tail rot. Numerous gram-negative bacterial species are responsible for fin and tail rot, which frequently develops in conjunction with other illnesses. Fin and tail rot can be difficult to treat, especially in more severe cases.


Fin rot is always caused by bad water conditions, but a fish’s stress can also make it worse. Fin and tail rot are more likely to happen to fish when they are handled, moved, crowded, or kept with more aggressive fish.


  • The fin edges turn white.
  • Fins appear ragged and split.
  • The bases of the fins became inflamed.
  • The entire fin may rot away.


Good water quality, feeding fresh food in small portions, and maintaining a constant water temperature can prevent fin rot. Maintaining a clean aquarium (for domestic fish) will also help prevent fin rot.


Examine your fish’s surroundings.

When your fish becomes ill, the first thing you must do is play detective and determine the cause. Fin rot may return if the cause of the problem is not eliminated. Examine the water parameters with an aquarium water test kit to identify any anomalies. Ensure that no environmental factors, such as an overly powerful filter, a sharp decor, or an improper temperature, are causing your fish stress.

Take corrective measures.

Once you know what’s wrong, get rid of the stressor right away so the fish can start to get better.

Clean the fish tank.

The medications require that you refrain from water changes during treatment, so clean the aquarium and remove fish waste as thoroughly as possible.

Medication is used to treat

We recommend using erythromycin, a broad-spectrum antibiotic that is effective against fin rot. Methylene blue is an effective antifungal treatment if your fish has also developed a secondary fungal infection.

Make your fish very comfortable.

Maintain a clean and comfortable environment for your fish to facilitate a speedy recovery. Medications can sometimes make it more difficult to breathe, so add an air stone or sponge filter to maintain oxygen levels.


Columnaris on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is Columnaris?

Columnaris disease, also known as saddleback disease and cotton wool disease, is caused by the gram-negative bacterium Flexibacter columnaris. This bacteria can infect a wide range of freshwater and marine fish species.

It spreads quickly and costs fish farms all over the world a lot of money and economic growth every year.

Typically, young fish are more prone to contracting this disease. Nonetheless, healthy and older fish may act as disease vectors.


poor quality of water. Inadequate diet. Shipping and handling cause anxiety. extremely hot water.


  • white or grayish spots or patches on the head, fins, or gills
  • Lesions on the back that may extend down the sides
  • Moldy or cottony-looking lesions on the mouth
  • Frayed fins


Due to the fact that columnaris bacteria thrive on organic wastes, outbreaks can be prevented through routine water changes and tank maintenance, including gravel vacuuming. A proper diet and the maintenance of good water quality will prevent the fish from becoming stressed and, consequently, more susceptible to infection. Putting new fish in quarantine and moving sick fish right away to quarantine will help stop the disease from being brought in or spreading.

Before each use, nets, specimen containers, and other aquarium equipment must be disinfected to prevent the spread of bacteria to other tanks. You can treat nets and other items with a commercially available Benzalkonium Chloride solution (called Net Dip or Net Soak), or you can soak them in a 3% hydrogen peroxide solution.


Antibiotics, water-borne chemicals, or both should be used to treat external infections. Copper sulfate, acriflavine, furan, and terramycin can be used to treat columnaris in water. Both as a bath treatment and as a food treatment for internal infections, terramycin has proven to be extremely effective. Salt may be added to the water (1 to 3 teaspoons per gallon) to reduce osmotic stress on fish caused by the bacteria-induced damage to the fish’s epithelium. Particularly, livebearers will benefit from the addition of salt; however, use caution when treating catfish, as many of them are extremely sensitive to it. When using salt, always err on the side of caution.


Hemorrhagic on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is Hemorrhagic?

Hemorrhage is blood loss caused by a ruptured blood vessel. The bleeding can be internal or external, and the blood loss can be minor or severe.

Hemorrhagic, also known as redmouth, causes severe bleeding within the mouth and eyes of fish. The disease can be prevented by disinfecting the aquarium to eliminate the bacteria Yersinia ruckeri, which causes the disease. Antibiotics, such as ampicillin, are capable of treating hemorrhagic. Because the infection is treatable, the mortality rate is low.


Cuts, puncture wounds, bone fractures, and traumatic brain injuries are examples of injuries. Violence, including gunshot wounds or stab wounds, or physical abuse blood vessel-infecting viruses, such as viral hemorrhagic fever.


  • Hemorrhaging (bleeding)
  • Bulging eyes.
  • Unusual behavior.
  • Anemia.
  • Bloated abdomens.
  • Rapid onset of death.


Do not allow your fish to come into contact with wild fish or fish from other farms. The VHS virus can be transmitted through direct contact with infected fish or contaminated water. When working on your farm, employees who have been around fish in other places, including their own homes, must follow strict biosecurity rules.


As with many other viral fish diseases, there is no treatment or cure for VHS. The virus is transmissible by diseased fish, non-symptomatic carriers, and broodstock gonadal fluids. Additionally, birds, bloodsucking parasites, and equipment may be sources of infection.


Dropsy on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is Dropsy?

Dropsy is the accumulation of fluid within a fish’s body cavity or tissues. As a symptom rather than a disease, it can be indicative of a variety of underlying conditions, such as bacterial infections, parasitic infections, or liver dysfunction.


Fish develop dropsy due to an accumulation of fluid within the body cavity or tissues. As a symptom rather than a disease in and of itself, it may indicate a variety of underlying conditions, such as bacterial infections, parasitic infections, or liver dysfunction.


  • Swelling of the abdomen
  • Eyes that are beginning to swell and bulge
  • Scales that starting to point outward instead of lying flush with their body giving a “pinecone” appearance
  • A loss of color in their gills
  • Clamping of the fins
  • A curve developing in their spine
  • Pale feces
  • Swelling near their anus
  • A loss of appetite
  • A lack of energy and movement


  1. Perform regular water changes.
  2. Keep the tank clean.
  3. Clean the filter regularly.
  4. Avoid overcrowding the tank.
  5. Do not overfeed.
  6. Use flake foods within one month of opening.
  7. Vary the diet.


  • Move sick fish to a hospital tank.
  • Add salt to the hospital tank, 1 tsp per gallon.
  • Feed fresh, high-quality foods.
  • Treat with antibiotics.


Popeye on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is Peopeye?

Popeye, also known as exophthalmia, is the enlargement of one or both eyes in aquarium fish. It is challenging to treat but simple to prevent.


Most frequently, fish popeye is caused by an injury, an infection, or inadequate aquarium water conditions. Infection is an additional cause of popeye. This is likely visible with both eyes. Multiple organisms, including bacteria, fungi, and parasites, can cause infection.


  • Protrusion of one or both eyeballs
  • Stretching of the eye socket
  • Discoloration or blood in the eyeball
  • Rupture of the eyeball
  • Cloudiness of the eyeball
  • Inactivity
  • Loss of appetite
  • Hiding or other behavioral changes
  • Swollen body
  • Clamped fins


Although Epsom salt can be used in both freshwater and saltwater aquariums, it is preferable to use it in a quarantine tank as opposed to the main aquarium. Similar antibiotics and antibacterials to those used to treat fin rot are effective in preventing corneal damage from developing into full-blown popeye.


If your fish has experienced a traumatic event, the best treatment is clean water, a healthy diet, removing the source of the trauma if possible, and time. Some injuries may be so severe that they prevent the eye from returning to its normal state, but your fish’s vision may still be fine.

Cloudy Eyes

Cloudy Eyes on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is Cloudy Eyes?

A cloudy eye is something that can occur in fish, typically as a result of eye damage (since fish typically do not have eyelids to protect their eyes from damage). Nonetheless, it can also result from a fish’s weakened immune system.

This usually looks like a cloudy layer, which can sometimes make the eye look white or gray.

This cloudiness may be present on the outer eye (on the cornea) or the inner eye of a fish with a damaged eye (the rest of the eye structure)


A simple abrasion to the cornea can cause a localized inflammatory response in the absence of eyelids. This is the most common cause of cloudy eyes in fish. As the fish’s immune system rushes to its aid, the cornea on the eye’s exterior can become cloudy.


  • The fish eye becomes cloudy almost to the point of whiteness and the fish lose vision


Always ensure that the water quality is optimal for the fish you are keeping, with levels of zero ammonia, zero nitrite, and low nitrate (around 20ppm or lower).

This is merely a guide and Tropical Fish Site assumes no responsibility for accurately diagnosing the problem with your tropical fish. There is frequently overlap between common tropical fish diseases, so compare them to ensure you have made the correct diagnosis.


This condition necessitates an investigation of water quality by performing routine water tests with a reliable test kit. Once the water quality is sufficient, the fish will typically recover within one to two weeks.


Furunculosis on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is furunculosis?

Furunculosis is a disease caused by the obligate bacterium Aeromonas salmonicida that affects both wild and cultured salmonids (trout and salmon). If the disease isn’t treated quickly with antibiotics, it can lead to bacterial septicemia, which often kills farmed fish.


Aeromonas salmonicida, a Gram-negative bacterium that causes furunculosis, is the most commonly encountered bacterial pathogen in cultured salmonids. The disease is found in freshwater all over the world and has also been reported in the marine environment. It has been observed in North America, Europe, Asia, and Africa. Furunculosis is distinguished by a generalized bacteremia and focal necrosis in muscle tissue known as furuncles.


  • Fish with furunculosis have darkened skin and large boils or sores as signs of the disease.


Adherence to a sound program of hatchery inspections and disease classification is a fundamental step in the prevention of serious communicable fish diseases.


On farms, the disease is controlled through medication or vaccination. Iodine is also used to clean the surface of fertilized eggs in order to prevent vertical transmission (passage of infection from parent to offspring).


Velvet on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is velvet?

Velvet disease is a fish disease caused by dinoflagellate parasites of the genera Amyloodinium and Oodinium in marine fish.


Velvet disease is a fish disease caused by dinoflagellate parasites of the genera Amyloodinium in marine fish and Oodinium in freshwater fish. The disease imparts a dusty, brownish-gold color to infected organisms.


The traditional clinical presentation of velvet is for the fish to appear to be dusted with a fine yellow or pale powder.In addition to respiratory distress, increased respiratory effort or rate, lethargy, and sudden death, other symptoms include respiratory distress, increased respiratory effort or rate, and lethargy.


To reduce the growth of Piscinoodinium, which causes freshwater velvet, increase the water temperature and turn off the lights. The safest and most effective treatment is salt immersion (a saltwater dip).


Copper is the most effective treatment for velvet in marine fish. Copper-based formulations of fish medications are available on the market. Follow the instructions on the label carefully.

Ich, Ick, or “White Spot Disease”

Ich, Ick, or "White Spot Disease" on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is Ich?

Ich, sometimes misspelled “Ick,” is an external protozoan parasite that causes multiple white spots on the skin and gills of freshwater fish. These spots frequently resemble white grains of salt or sugar strewn across the body, gills, and fins of the fish. Fish with Ich also often hide, rub or scratch themselves against aquarium decorations or other things, and refuse to eat.

Ich is a prevalent parasitic infection of freshwater fish and one of the few visible fish parasites. However, other non-parasitic causes of white spots on fish must be ruled out prior to initiating treatment. Understanding the life cycle of the parasite is essential for effective treatment. Ich-infected fish are difficult, but not impossible, to heal.


Ich, also known as white spot disease, is caused by the protozoan parasite Ichthyophthirius multifiliis, whose Latin name translates to “fish louse with many offspring.” Cryptocaryon irritans causes Ich, or white spot disease, in saltwater environments. The complex life cycles of both parasites make them difficult to treat. The large feeding stage (trophont) of the parasite is visible as white spots on the fish’s body but is extremely resistant to treatment. 1 The invisible front stage is the only stage of the parasite’s lifecycle that is susceptible to treatment. It only takes one trophont feeding on a fish to reproduce (as a toront) and release 1,000 new infective organisms (the toront) into an aquarium, so infestations can spread rapidly. The life cycle is temperature-dependent, with shorter stages in warmer water and longer stages in cooler water.


  • Small white spots on the fish’s body or fins
  • Fish flashing or scratching against objects in their environment
  • Bruising or scale loss secondary to flashing
  • Lethargic and increased respiratory effort
  • Sudden death (which can happen to several fish in the same aquarium)


  1. New fish should be quarantined for four to six weeks (depending on temperature).
  2. quarantine new invertebrates previously kept with fish for two to four weeks.
  3. quarantine all new plants before adding them to the tank (two weeks with no fish).


  1. Remove any carbon from the filter before beginning any treatment, as it will render the medication useless.
  2. Raise the temperature of the aquarium by 2 degrees Celsius or 4 degrees Fahrenheit.
  3. Add aquarium salt to the water…
  4. Add a medication to the water.

Anchor Worms

Anchor Worms on Betta Fish: Cause, Symptoms, Prevention and Treatment

What are anchor worms?

Anchor worms are parasites that live on the outside of a fish’s body and eat its food.


Anchor worms are contagious among fish and spread when a new fish carrying juvenile anchor worms or a reproductively active female is introduced to an aquarium. The spread of this parasite is accelerated in the absence of proper quarantine.


A fish infected with anchor worms will have irritated skin that is red and inflamed. Upon closer inspection, you can see the parasite’s body protruding, appearing as whitish-green threads. tion, the parasite’s body can be seen protruding as whitish-green threads.Additionally, the fish will rub or brush against objects in an effort to eliminate the anchor worm (s).


The most effective method for preventing anchor worms is to quarantine all new aquarium inhabitants. If you see any anchor worms in a tank of fish you intend to purchase, you should assume that they are all infected.


The anchor worm can be extracted from the fish’s skin by carefully pulling it out. The infected area is then treated with an antibiotic ointment applied topically. The pond or aquarium must then be sanitized and disinfected to eliminate any adult parasites, larvae, or eggs.

Hole in the Head

Hole in the Head on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is “Hole in the Head”?

Hole-in-the-head disease is distinguished by the presence of small, dark holes or depressed areas around the head and lateral line in numerous freshwater and marine species. There may be a few or many available spots. They may all be the same hue, or they may vary in hue, size, and depth.


Stress is the leading cause of “hole in the head” disease. Fish can experience stress due to a variety of environmental factors, including water quality, diet, aggression, space, and others. If a stressor persists in an environment from which a fish cannot escape, a chronic stress pathway is activated, resulting in reduced reproduction, growth, and immune function. Once the immune system has been compromised, bacteria on the fish’s skin can exploit the weakened defenses to cause localized infections.


Hole-in-the-head disease is distinguished by the presence of small, dark holes or depressed areas around the head and lateral line in numerous freshwater and marine species. There may be a few or many available spots. They may all be the same hue, or they may vary in hue, size, and depth.


A hole in the head can be fixed by getting rid of all the activated carbon and changing a lot of water. To lessen the effects of activated carbon, you may need to change more than 90% of the water. Most of the time, fish are cured by moving them to a new aquarium where they have never had HLLE.


The main goal of treating hole in the head disease is to get rid of the main cause of stress.

Improve water quality

Insufficient water quality is the leading cause of hole-in-the-head disease. Any method for treating a hole in the head should begin with a comprehensive analysis of the water’s chemistry. Replace those ineffective test strips with a liquid-based test kit purchased within the previous year. All of your ammonia, nitrite, nitrate, pH, kH, gH, temperature, and salinity levels should be within the acceptable range. If they are not, you must take action to improve the quality of your water. Typically, this alone is sufficient to heal your fish.

Provide a sufficient diet

Diets for different fish species can vary greatly. Ensure that whatever you are feeding has been opened within the past six months. After this period, the concentration of water-soluble vitamins, including vitamin C, significantly decreased. It makes no sense to purchase fish food in bulk! As they do not use the more stable form for fish foods, freezing will only destroy a portion of the water-soluble vitamins.

Confront Bullies

Bullies are aggressive fish that rob other fish of food and resources. Don’t be deceived by size!We have observed very small, aggressive fish nibbling at the gills of larger fish during feeding times, causing them stress and a hole in the head. If you are unable to spread out the meal, it is time to relocate the bullies. Some fish, regardless of how they are “supposed” to behave around others, do not follow the rules and do not get along with others.

Sensational Excess

With their sensitive hearing and lateral line organs, fish are easily stressed by noise pollution. This can include the sound of filtration components, televisions, stereos, and doors slamming. If you have any of these elements in close proximity to your fish tank, consider moving them or providing insulation for your fish.

Swim Bladder Disorder or Flipover

Swim Bladder Disorder on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is Swim Bladder Disorder?

This disease, which is also called “flipover,” makes the fish float on top of the water. The sick fish swims sideways or upside down, and it can also lie at the bottom of the tank.


There are many things that can cause this disorder, from environmental factors to problems with feeding, such as:

  • Rapidly eating, overeating, constipation, or gulping air may occur with floating foods to cause an extended belly and displace the swim bladder. Eating freeze-dried or dry flakes of food that expand when they become wet can also lead to an enlarged stomach or intestinal tract.
  • Other abdominal organs may become enlarged and affect the bladder. Cysts in the kidneys, fatty deposits in the liver, or egg binding in female fish can result in sufficient enlargement to affect the swim bladder.
  • Low water temperatures can slow digestion, resulting in gastrointestinal tract enlargement, which puts pressure on the swim bladder.
  • Parasites or bacterial infections can inflame the bladder as well.
  • Occasionally, a hard blow from striking an object in the tank, a fight, or a fall can damage the swim bladder.
  • Rarely are fish born with birth defects that affect the swim bladder, but in these cases, symptoms are usually present at an early age.


  • sinking to the bottom of the tank (or floating by standing on its head at the bottom of the tank).
  • Floating to the tank’s top
  • struggling to stay upright.
  • Fish swimming upside down
  • Fish swimming sideways
  • Distended belly
  • Curved back
  • Changed appetite


It is well known that when water conditions are bad, fish are more likely to get sick. Keeping the tank clean and changing the water often can help prevent swim bladder disease.
Keeping the water temperature a bit higher will help digestion and may help prevent constipation.
Feed only high-quality foods, and soak dried foods for a few minutes before feeding.
Always let frozen foods thaw completely before putting them in the tank. If fish swallow air when they eat at the surface, try switching to foods that sink.
Avoid overeating at all costs.Feed the fish smaller amounts so they don’t overeat, and watch how much you feed them over the course of a week.


Treatment involves water maintenance, feeding changes, and possible antibiotics.

  • Let the fish fast: If an enlarged stomach or intestine is thought to be the cause of a swim bladder disease, the first course of action is to not feed the fish for three days.
  • Fix the water temperature: At the same time the fish is fasting, increase the water temperature to 78–80 degrees Fahrenheit and leave it there during treatment.
  • Feed the fish peas: On the fourth day, feed the fish a cooked and skinned pea. Frozen peas are ideal for this, as they can be microwaved or boiled for a few seconds to thaw, resulting in the proper consistency (not too soft but not too firm). Remove the skin, and then serve the pea with the fish. You can continue to feed one pea a day for a few days and then switch to a species-appropriate food, but avoid flakes or pellets that float.
  • Antibiotics: If an infection is thought to be the cause of a fish’s swim bladder disease, treatment with a broad-spectrum antibiotic may help. For this, you’ll need to visit your veterinarian.

Other supportive treatments (regardless of the cause) can include the following:

  • Keep the water especially clean and the temperatures between 78 and 80 degrees Fahrenheit.
  • Add a small amount of aquarium salt to the tank.
  • Reduce the water level to make it easier for the fish to move around within the tank.
  • Reduce water flow in tanks with a strong current.
  • If the affected fish floats with part of its body constantly exposed to the air, applying a bit of Stress Coat water conditioner (which helps improve the fish’s slime coat) can help avoid the development of sores and red spots.

Betta Tumors

Betta Tumors on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is a Betta tumor?

A betta fish tumor is an external or internal growth with a lumpy appearance on the skin. External tumors are the easiest for Betta fish owners to recognize because they are visible on the fish’s scales.

Internal tumors are frequently invisible, especially when they are small. Consequently, you will need to observe your betta’s behavior to determine if something is wrong.

Tumors range in size from so small that they are barely visible to so large that it appears as if your betta is growing another fish on them.


Many factors can cause tumors in betta fish, including:

  • Genetic predisposition
  • Poor water parameters
  • Low-quality diet
  • Viral infections

Not all tumor growths are cancerous.

Instead, if your betta’s tumor has a white appearance, it could be a benign abscess or ulcer. Fungus infections can also create the appearance of cotton-like growths on your Betta’s body.


The most common betta fish tumor symptom is seeing a physical growth on your betta’s body. Tumors can grow on any part of a betta fish.

In some cases, there might be a single growth. Other scenarios involve multiple tumors growing in separate locations or clumping together.

Aside from a round growth emerging from your pet’s body, other tumor symptoms include:

  • Lethargy
  • inability to swim properly
  • Lack of appetite
  • Difficulty breathing
  • Overall appearance of poor health

Sometimes a tumor starts as a small, discolored spot. You may see a tumor growing directly on the scales or lifting the scales beneath your betta fish’s skin.


It can be hard to treat betta fish tumors, so your best course of action is to prevent them from forming in the first place. Fortunately, there are a few things you can do to reduce the risk of tumor development and promote good health in your breast.

For new fish, use a quarantine tank.

Before you add new fish or invertebrates to your betta fish tank, you should house them in a quarantine tank for at least two weeks so you can treat them for any illnesses or diseases that may develop in that timeframe.

This will help you keep your betta healthy by preventing the spread of bacterial, viral, and fungal infections.

In addition, if you’re introducing fresh plants to your tank, either quarantine them for around a week or clean aquarium plants using a bleach and water solution (3% hydrogen peroxide mixed with water will also work).

Purchase From a Trustworthy Betta Breeder

Some Betta fish are genetically predisposed to external and internal tumors, but you can lessen the chance of your betta developing tumor growths by purchasing it from a reputable breeder or a good local fish store.

Inbred fish and those from poor stock are more likely to develop lumps or other health issues.

Only buy specimens that look healthy and don’t show signs of sickness, such as lethargy, rapid breathing, dull coloration, torn fins or tails, lesions on the betta’s side, or inflammation on the fish’s gills.

Provide A Nutritious And Healthful Diet

Providing your betta fish with a well-balanced, protein-rich diet will help keep your pet protected from illness and disease, as well as strengthen their immune system. This can vastly reduce the risk that many Betta fish tumors cause.

Make sure you offer your betta a variety of freeze-dried, live, and frozen foods like betta pellets, mosquito larvae, daphnia, and bloodworms. You can also feed them peas every now and then to ease constipation, prevent swim bladder disease, and keep their digestive system healthy.

Keep your tank water clean.

Many issues are tied to poor water quality and a dirty tank, including swim bladder infection, gill hyperplasia, and certain Betta fish tumor causes like bacterial infections.

Gill hyperplasia, which can cause tumor-like growths on your betta’s gills, is often caused by parasites, bacterial infections, or unsanitary living conditions. Fish with gill hyperplasia will have difficulty breathing properly, and, in severe cases, it can be fatal.

The best way to counteract issues with betta fish gills and other health conditions is by keeping your tank water clean with frequent water changes.

Most fish keepers perform weekly water changes, though the size and bioload of your tank will need to be considered. Smaller, overstocked tanks will need more maintenance than larger, understocked ones.


Sadly, there isn’t much you can do to treat a cancerous tumor in a betta fish.

If you live near a veterinarian with experience working with fish, they might be able to attempt surgery to remove the tumor. However, such a situation is uncomfortable for your fish, and the success rates are next to none.

As with humans, a tumor can also regrow. So, even if your veterinarian successfully removes the tumor and your betta fish recovers, there’s no guarantee that it will remain gone for good.

Betta fish only have a lifespan of two to five years, and tumor surgery is often expensive. So, most betta owners opt to keep their fish as comfortable as possible with their tumor in place for the duration of their lives.


Mycobacteria on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is a Mycobacteria?

Mycobacteria is most frequently linked to tuberculosis. It persists in almost all aquatic environments as a non-harmful environmental contaminant. However, certain species, including M. marinum, M. fortuitum, and M. chelonae, can infect fish. M. marinum is present in both freshwater and marine ecosystems. It is transmitted through direct contact and internal organs after death.


Sadly, the clinical manifestations of a mycobacterial infection are extremely vague. It is usually accompanied by wasting, loss of body condition, lethargy, and anorexia. Other symptoms include loss of scales, skin ulcers, a dropsy-like appearance, reproductive difficulties, and a multitude of secondary infections.


It is very important to use quarantine and disinfection protocols to stop the spread of disease. Most of the time, the infected fish are put to sleep, and the system they were kept in is cleaned with the right chemicals. At the moment, there are no tests that don’t kill the fish to check for mycobacterial diseases.


The most unfortunate aspect of this infection is that there are no treatments available. The bacteria can be tolerated by fish in environments with low stress and high water quality, but the fish will eventually succumb to the disease. It is recommended that the entire system be decontaminated with a disinfectant that is able to penetrate mycobacteria. Not all disinfectants are effective against mycobacteria. Prevention is essential through proper quarantine and, if necessary, the sacrifice of some individuals for histopathology testing.


Constipation on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is constipation?

Constipation in fish is typically revealed by bloating and the production of stringy feces. Normal fish feces will immediately fall to the substrate; constipated fish feces will appear stringy and hang from the fish.


Constipation is a common problem in Betta fish, and it can be caused by things like a diet high in fiber, not changing the water enough, or a dirty tank. Bettas often get constipated because they are “sit and wait” predators. This means they often swallow their food whole, which can cause indigestion.


Constipation can make a fish’s stomach swell up, make it hard for the fish to swim, or make it refuse to eat.


Since constipation is caused by not eating enough fiber, the best way to treat it is to feed your fish high-fiber foods. These high-fiber foods will help your fish get rid of the waste that has built up and get back to normal digestion.


If you think your fish is having trouble going to the bathroom, the best thing to do is change the water and feed your fish high-quality food that is easy to digest. You can also give your fish a pea, which will help them get rid of their diarrhea.

Ammonia Poisoning

Ammonia Poisoning on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is ammonia poisoning?

Ammonia poisoning happens when the nitrogen cycle is thrown off by a high ph level in a fish tank. In the best water conditions, there shouldn’t be any ammonia. But this problem can be caused by both tap water and the breakdown of organic matter inside the tank.


Ammonia poisoning can be caused by a number of different things. These include:

  • You are not cycling your tank.
  • Overstocking your tank with too many fish
  • Overfeeding your fish
  • Adding untreated tap water
  • Insufficient filtration
  • Incorrect pH levels

Let’s look at each of these potential problems so that you can avoid them.


  • increased mucous production.
  • Red or bleeding gills
  • The color of the body darkens.
  • increased respiration rates, and fish seem to “gasp” air at the surface of the water.
  • Secondary infections.
  • Death.


  1. Establish a beneficial bacteria colony and the nitrogen cycle.
  2. Avoid overfeeding fish and overcrowding the tank…
  3. Change the water and clean the tank on a regular basis…
  4. Regularly test your water for ammonia.
  5. Maintain a proper water PH.


  • Regular water changes (25–50%)  dilute the ammonia levels in the water.
  • Add chemical filtration. activated charcoal (for freshwater or marine tanks)…
  • Add commercial chemicals (e.g., ammo-lock).

Slime Disease

Slime Disease on Betta Fish: Cause, Symptoms, Prevention and Treatment

What exactly is slime disease?

This parasitic disease is marked by making too much mucus, which looks like a gray, white, or blue coating. If your fish has this problem, it will also breathe quickly. This is because the fish is stressed.


Several different protozoan parasites can cause slime disease in aquarium fish. Ichthyobodo necator, Ichthyobodo pyriformis, Chilodonella spp., and Trichodina spp. are some of these.


When aquarium fish make more mucus, it will show up as cloudy patches on their skin, especially along their sides. Because aquarium fish with this problem make more mucus around their gills, they often show signs of breathing problems like heavy or labored breathing.


  1. You should check your water for pH levels and perform a 30 to 50 percent water change.


Aquarium fish with slime disease need to be treated right away because heavy infections make it easier for secondary diseases like finrot to take hold. When that happens, the aquarium fish are in a lot worse shape.

Fish Lice

Fish Lice on Betta Fish: Cause, Symptoms, Prevention and Treatment

What is fish lice?

Fish lice, which belong to the family Argulidae and are made up of branchiuran crustaceans, live on both saltwater and freshwater fish. Argulus spp. can be a major threat to the health of fish because large numbers of them can cause a lot of sickness and death. Also, fish lice are known to spread other diseases between fish.


Like anchor worms and flukes, fish lice are often brought in by new fish or plants that haven’t been quarantined. Symptoms include itching and small green specks that move around the fish in safe places like behind the fins, near the eyes, or on the gills.


Fish that don’t have visible lice may show other signs of being infested, such as spot or pinpoint bleeding, anemia, loss of fins and scales, increased mucus production, lack of energy, erratic swimming, and poor body condition. Fish may rub against surfaces to try to get rid of parasites or to stop being bothered.


Even when precautions are taken, fish lice can be hard to avoid. Before adding new fish to an existing system, it is important to check them out and keep them in a quarantine tank for four to six weeks. Also, you should put live freshwater plants in a separate room for two weeks because they may also have lice.


Organophosphates are the best way to get rid of fish lice. They are usually given in two or three doses, one week apart, to kill the emerging larvae and juveniles. Diflubenzuron (Dimilin, Chemtura) has been shown to be an effective treatment for adults, but it is a pesticide that can only be used in certain ways.

Gill Flukes

Gill Flukes on Betta Fish: Cause, Symptoms, Prevention and Treatment

What are Gill Flukes?

Gill flukes (Dactylogyrus) and skin flukes (Gyrodactylus) are common parasites that affect fish. Like popular community fish, they are split between livebearers and egg layers, but that’s where the similarities end.


Parasites often get into an area because of bad water quality. Fish get stressed out by dirty water, which weakens their immune system and makes them more likely to get sick. Bad diet: Fish that eat food that has gone bad or isn’t clean may get parasites.


  • Missing scales.
  • Red spots.
  • Excess mucus.
  • hazy look to the skin.
  • Flashing behavior.
  • Lethargy.
  • Decreased appetite.


To keep your fish from getting flukes, give them a low-stress environment. This means keeping the water clean and well-maintained, giving the fish a healthy diet, and following strict quarantine rules for any new fish added to the tank.


Since flukes are often the cause of ulcers and other secondary infections, you should try to get rid of them before using antibacterial or antifungal drugs. There are many ways to treat flukes, but the ones that contain praziquantel work the best.

Red Streaks

Red Streaks on Betta Fish: Cause, Symptoms, Prevention and Treatment

What are Red Streaks?

Bacterial septicemia is one of the less common diseases that Pseudomonas or Streptococcus bacteria can cause in Betta fish.


This skin infection can kill a fish that is already stressed from a bad diet or a dirty environment. To make sure that all of the parasites and carrier cysts are killed, the medicine must be given for 10–14 days.


  • White spots or bloody red streaks are typical symptoms of Ich


Some suggested treatments are to clean the aquarium and add a fish disinfectant, put antibiotics in the fish food, or put antibiotics in the water.


When outbreaks happen in small, closed bodies of water, liming the water and making the water quality better, along with removing infected fish, is often enough to cut down on deaths.

Tips for Treating Diseases in Sick Betta Fish

Following these guidelines will increase your pet’s chance of recovery.

Sick fish in a hospital tank in Quaratine

Before returning diseased fish to their aquariums, they should be quarantined to prevent the spread of the infection. A hospital tank should be at least 10 gallons in size and have a bare bottom. In addition to chemical filtration, it must possess an established biological filter. In addition, a heater and air pump will be required to ensure adequate water circulation. UV sterilizers are not required, but they are an option.

A quarantine system need not be complicated or expensive. Maintain its cleanliness, replace the water frequently, and monitor the water’s chemistry as well as the fish’s health. Maintain low light levels and provide ample cover, such as flower pots and other decorative objects, particularly if the fish are fearful or anxious.

Confirm that the tank is secure and located in a quiet area of the house. Because these arrangements are so simple, it is much easier to look at a patient’s symptoms and figure out what is wrong with them.

Pick the Right Medicine for Your Betta’s Ailment

Your local aquarium shop will carry medications for a wide range of diseases; therefore, you should seek assistance in selecting the correct one. True hobbyists at these stores are happy to help you figure out what’s wrong with your fish and tell you how to treat it.

Follow the directions on the medication’s label.

Follow the directions on the label of the medication precisely. Do not estimate measurements; medications indicate the exact amount to use per gallon or per tank size. Depending on the size of your aquarium, you may need to adjust the dosage accordingly. Keep in mind that improper administration of certain medications may result in the death of the fish.

Complete the Treatment

Follow through with the prescribed treatment. The most common error is discontinuing the medication as soon as the patient begins to improve. This frequently allows the disease to regain a foothold, and when treatment is resumed, the disease typically develops resistance to the medication.


In this article, we looked at a number of diseases and bacterial infections that can affect betta fish, as well as their causes, treatments, and ways to avoid them.

Always keep a close eye on your Betta fish, and the water conditions in their community tank are one of the most important reminders.

The majority of common diseases can be avoided with proper betta fish care and maintenance and can be treated if detected and addressed promptly.

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