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Betta fish will occasionally get sick and suffer from parasitic, bacterial or fungal diseases. If you have a sick betta fish – quick identification, care and treatment will minimize potential damage and keep your colorful friend swimming happily for years to come. The most prevalent betta fish diseases and their symptoms and pictures are listed below, including an easy identification chart.
The absolute best way to keep your betta fish from getting sick is to keep them happy and healthy by following proper care guidelines for betta fish husbandry. Just like you wouldn’t want to be freezing or living in a dirty and cramped home, your betta fish doesn’t either!
Water cleanliness and temperature, breeding abnormalities, tank size, feeding habits, and stress are some of the leading causes of sickness and disease in bettas. With proper tank maintenance and care you can prevent a lot of common illnesses before they start.
Common Betta Fish Diseases w/ Treatment:
|Betta Behavior||Loss of appetite (stops eating)||This is one of the first signs of stress and/or illness||Treatment will vary depending on what’s causing it, however you should start by ensuring clean water and tropical water temperatures. Get a heater to maintain consistent temperatures.|
|Floating on his or her side or can’t swim right||Constipation or Swim Bladder Disorder (SBD)||If constipation, remember not to overfeed, and consider fasting for 2-3 days to see if the issue subsides. If the problem persists or gets worse, consider feeding a pea or administering an antibiotic like Mardel Maracyn 2 if you suspect an bacterial infection of the swim bladder.|
|Stringy or lack of poop||Constipation||Reduce amount fed, consider fasting for 2-3 days.|
|Sluggish and withdrawn, may sit on the bottom||Another first sign of stress or illness. It is also possible that it’s just your betta’s temperament.||Treatment will depend on the cause. Start first with ensuring clean water and a tropical temperature. Betta’s that are too cold will be sluggish to preserve energy and heat. Get a heater to maintain consistent temperatures.|
|Darting or spastic swimming||May be a parasitic disease or exposure to a toxin in the water.||Ensure clean water that is free of chlorine. Consider administering an anti-parasitic or anti-biotic. You can try bettafix|
|Betta Fins||Black or red fin and tail edges that are not normal colorings and are receding.||Fin or Tail Rot||Make sure the water is clean with proper tropical temperature range. If the rot gets worse, you may use an antibiotic such as antibiotic like Mardel Maracyn 2|
|Clamping of the fins||Initial sign of stress or Illness. Usually accompanied with lack of appetite and lethargy. If ignored could lead to disease.||Treatment can vary but the first step is to ensure clean water with the proper tropical temperature range to see if the clamping subsides. Get a heater to maintain consistent temperatures.|
|Fins or tail missing chunks||Fin/Tail Rot or Fin/Tail Biting||See fin rot above. Fin and tail biting is common amongst betta fish and leads to missing portions of fin tissue. Reduce boredom or stress.|
|Betta Body||Black tissues or redness and red streaks||Fungal infection or the disease Septicemia. Septicemia is very hard to diagnose in colored betta’s and is not common.||Make sure your tank’s water is clean and consider using an anti-fungal for fungal infections, or an antibiotic like Mardel Maracyn 2 for septicemia.|
|Bloated or bulging stomach||Constipation or Dropsy||Constipation is caused by overfeeding or not varying diet. Do not overfeed. Fasting may be required for several days. If you suspect it’s dropsy, ensure clean water and consider administering an epsom salt bath (no dyes, unscented) in a quarantine tank. Antibiotics may also be necessary, antibiotic like Mardel Maracyn 2. Dropsy is usually fatal however.|
|Color fading or complete color loss||This is a general sign of stress or illness.||Treatment will vary, but first steps should be checking water parameters and temperature. Get a heater to maintain consistent temperatures.|
|Open cut or sore, missing scales||Physical injury||Make sure the water is clean and the temperature is within tropical range for healing. Also consider administering bettafix.|
|Wool-like or fuzzy growths along the body. May also affect the gills.||Columnaris or overactive slime coat||Start with clean water and lower the tank temperature if it’s too high. If these don’t work, you may try an anti-fungal like this one.|
|Goldish-yellow rust-like dusting. Best identified using a flashlight.||Velvet (see photo below)||You should consider administering bettafix to help with recovery and use Mardel Copper Safe.|
|Horizontal Stripes||A sign of stress||You should make sure your betta is not in direct sunlight, the water is clean with proper tropical temperatures, and that it can get to the surface for air. Also, no quick changes in water temperature, movement of the tank or ongoing loud noises. This is most often associated with feeling threatened.|
|A Lump or bump that gets increasingly larger and is not the result of a physical wound.||Tumor||There is little you can do without spending a lot of money to reverse a tumor. Ensure proper clean water and tropical water temperatures.|
|Small white dots||Ich / Ick||Since Ich or Ick is a parasite treating your betta as a host, you’ll need to administer an anti-parasitic like Rid Ich Plus or Mardel Copper Safe. You should also slowly raise the temperature if possible (of the water temporarily) to 85 degrees fahrenheit to kill off any remaining Ich parasites.|
|Severely raised scales||Dropsy||Ensure clean water and tropical water temperature. Administer an epsom salt bath in a quarantine tank and an antibiotic like Mardel Maracyn 2.|
|Betta Eyes||Swollen or bulging eye||Popeye||Ensure clean water parameters and administer an antibiotic like Mardel Maracyn 2.|
|Cloudy-looking||May be caused by injury or an infection.||Start by ensuring clean water and if that doesn’t help, consider administering bettafix to help with healing.|
|Betta Head||A physical hole||“Hole in Head”||Ensure proper nutrition and clean water.|
|Betta Gills||Open operculum||May be Gill Hyperplasia or a sign of a parasite.||Ensure the tank’s water is clean and consider adding aquarium salt or administering an anti-parasitic.|
|Rapid or Labored Breathing||Also a sign of Gill Hyperplasia or an infection||Ensure the tank’s water is clean and consider adding aquarium salt or administering an antibiotic.|
Betta Disease Pictures and Snyopsis
Some betta diseases can be treated easily with aquarium salt or antibiotics. Check your fish daily for anything abnormal. A great time to do this is during feedings and tank cleanings. Sometimes the symptoms are noticeable, like scales that look like a pine cone or a dimming of your betta’s colors, but others might be more difficult to identify.
Try to learn your fish’s personality, so you’ll be able to know if they’re acting differently or even refusing to eat. These signs are usually an initial indicator of a problem. After diagnosis of a disease, you’ll need to follow the treatment options right away to limit the chances of increasingly malignant outcomes.
Columnaris (Cotton Wool or Mouth Fungus)
Bacteria that is both beneficial and harmful (columnaris) is present in your betta’s aquarium. Under stressful habitat conditions (e.g. overcrowded) and unmaintained water, bacteria may enter through lacerations, the mouth or gills. Visible sometimes stringy cottony patches on the mouth, gills, or fins along the body will be present. Accelerated symptoms include visible lesions and gill damage.
Dropsy can be caused by numerous issues including viral disease, parasites, poor nutrition, and bacteria. It is also prevalent amongst caretakers who feed their betta’s live food.
On its own it is not a disease, but rather the symptom of what’s going on inside the betta fish’s body from other ailments. These ailments include: fluid build up and the swelling of failing organs (liver and kidney). Dropsy is severe and visible from above. You’ll notice extreme swelling in the abdominal area and outward flaring scales that resemble a pine cone. This is shown in the photo above and in the full video here.
While this disease can be contagious, in most cases it is not. The bacteria that triggered internal issues is contagious though and can harm other community tank members. Another symptom of dropsy is the tendency for your fish to stay close to the surface to easily get oxygen. Their appetite will also be virtually non-existent.
Based on the amount of cases, fin rot (or melt) is likely the most common betta fish disease. It may be confused with tail biting resulting from boredom too. Their long and beautiful fins are susceptible to tears on tank decorations, and health problems from poor water quality.
Upon inspection, the tail (caudal) or other fins will show visible signs of the disease. To learn what each betta fin is called, visit the anatomy page. Continue to monitor for slow decay, rips, recession and red or black edges along the affected areas.
Typical behavior and personality does not usually change unless the betta is suffering from other ailments too. And to answer your next question, yes their fins can grow back!
Hole in the Head
Just as the name suggests, betta fish can suffer from small holes that over time become increasingly larger lesions. These cavities are easily visible and tend to travel along the lateral line of bettas. If diagnosed soon enough it can be cured, like most betta diseases, but in later stages it becomes increasingly dangerous. Usually caused by improper nutrition or ecosystem cleanliness, early signs include small sores, dents or pin-holes on the surface of the betta’s head above its eyes.
One of the most common betta fish diseases is Ich and is caused by host eating parasites. It is characterized by small white dots that are similar in size to that of a sugar granule. These spots are highly visible to the naked eye and appear along the body and fins of a betta fish.
It’s a very preventable and treatable disease that is however uncomfortable for your betta. You may notice them rubbing against objects in the tank in an attempt to get the parasites off their body.
This disease affects the betta fish’s eye and will cause one or both to bulge out. It can be very startling the first time you see these symptoms, but it is treatable. The most common cause of popeye is prolonged dirty and poor water quality from improper care.
If you monitor the quality of your betta’s water and don’t feed him or her live food, you should never experience it. Strictly popeye can be cured without long-term damage or loss of sight, but sometimes it is a sign of tuberculosis. Tuberculosis is a more serious and always fatal betta disease.
Septicemia (Red Streaks)
Most commonly affecting betta fish who are stressed (e.g. continual and quick changes in water temperature) or have been wounded, septicemia is an infection from bacteria. Adding new community fish without quarantining, or feeding of infected food can lead to the betta fish disease septicemia.
It is not contagious and can be diagnosed by visible red streaks or bloody marks along the body of a betta. High levels of nitrite causing nitrite poisoning can also lead to red stripes. Rule this out first by conducting a water test and determining existing nitrite levels.
Wounds that are a healthy pink are normal, but if you notice a wound that is dark in color or has other signs of abnormal coloration it could be septicemia. Owners have noted this infection attacking betta’s who are already suffering from popeye too.
If left untreated it could lead to organ failure and dropsy so be careful. Also note that septicemia could be virtually impossible to detect on red-colored betta fish.
Swim Bladder Disorder (SBD)
SBD does not hurt a betta fish but it does need attention. The swim bladder is found between the stomach and the fish’s tail. Overfeeding can lead to bloating, constipation, and swim bladder disorder from the digestive tract pressing towards the swim bladder.
This is very common among betta’s in captivity because of misinformation or lack of knowledge around how much to feed a betta fish. The instructions on the back of food containers can be misleading and usually represents an over-estimation.
SBD is not contagious and it usually clears up on its own. This disorder is more prevalent in young fry and select breeds like the double tail betta. Symptoms include: difficulty swimming, constantly being in an “S” shape, changing depths, the inability to leave the surface of the water or the preference of staying on the bottom, and the inability to swim horizontally. Shorter swim bladders lead to bottom sliding and swollen symptoms lead to more floating.
Velvet is a parasitic disease that causes a goldish-yellow or rust-like sprinkling of color on the betta’s body, gills, fins or all three. It is hard to diagnose and is best identified by using a light source such as a flashlight and shining it on the betta. Some betta fish exhibit marbling and unique coloring, thus you must eliminate this as their pre-existing colors.
Bettas with velvet will often dart around the tank looking for spots to rub themselves on (just like Ich) in an attempt to get the parasites off. If left untreated, it can lead to death as it continues to attack the betta.
Velvet is highly contagious to other community fish, especially in sororities. If you think your betta has velvet you should move them to a hospital tank for treatment right away. Also treat the community tank even if the other fish appear to be healthy and without signs of the disease (better safe than sorry).
Velvet is most often caused by ongoing stressors, poor water conditions, and prolonged exposure to colder than tropical water temperatures.
Prevent Betta Diseases Before They Start
The list above is meant to provide details and pictures around the most common betta diseases that you may encounter as an owner. It is not an exhaustive list of all diseases. The best way to deal with diseases and illnesses is to not get them in the first place (proactive vs. reactive).
It is your responsibility to learn how to care for and provide a suitable ecosystem for your betta fish. With that said, diseases amongst betta fish can and do happen somewhat frequently.
Quick identification and treatment will ensure that you are providing the best care and chances for overcoming the problem.
If you still have a question, please post it in the comments section below.