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If you have a sick betta fish, you’re probably feeling a little scared, confused, and anxious about how this happened. While relatively hardy fish, betta fish can suffer from parasitic, bacterial, and fungal diseases just like any other freshwater fish.
Quick identification and treatment will minimize potential damage and get your colorful friend swimming happily again. The best way to keep your betta fish from getting sick is to keep them happy and healthy by following proper betta fish care.
It’s always better to be proactive than reactive. Just like you wouldn’t want to be freezing or living in a dirty and cramped home, your betta fish doesn’t either! That would eventually get you sick too.
Sick Betta Fish Behavior
- Lethargic: Inactive, lazy, lacks aggression, hiding
- Refusal to eat for extended periods of time (e.g. days)
- Faded colors, mainly in male bettas
- Labored breathing
- Damaged fins
- Clamped fins
Certain behaviors are linked to a stressed or sick betta fish and not necessarily a full-blown disease yet. Identifying these behaviors (listed above) is the easiest way to tell if your betta fish is sick. Noticing these behaviors and correcting the problems early is very important. Failure to do so could exacerbate the problem and lead to more severe complications.
Betta Fish Diseases
The most prevalent betta diseases are listed below…
|Columnaris||Cottony white growths along the body and/or gills.||Stress, poor water quality.||Clean water and/or Anti-fungal medication.|
|Dropsy||Extreme body swelling and pineconing of scales.||Virus, bacterial infection, or parasites.||Kanamycin Sulfate or
|Hole in Head||Visible holes above the eyes.||Poor nutrition and water quality.||Clean water and proper betta fish food.|
|Ich/Ick||Small white dots on body and fins, rubbing on decor.||Poor water quality, stress, or contagious companions.||Clean water and
Rid Ich Plus or
Mardel Copper Safe
|Fin & Tail Rot||Black/Red tattered and receding fin edges.||Poor water quality.||Clean water and aquarium salt administration. Severe cases require Maracyn II antibiotics.|
|Popeye||Bulging eye.||Prolonged exposure to bad water quality, or Tuberculosis.||Clean water and Maracyn II antibiotic.|
|Swim Bladder Disorder||Floating on side, difficulty swimming or regulating depth.||Genetics, overfeeding, or bacterial infection.||Fasting 2-3 days. Maracyn II antibiotic.|
|Tumor||Lump or bump.||Varies||Outlook is usually fatal.|
|Velvet||Goldish-yellow rust-like dusting. Rubbing on decor.||Stress, cold and poor water quality.||Clean water, 76-81 degrees Fahrenheit. Mardel Copper Safe.|
After diagnosis, you’ll need to follow the treatment options right away and always strictly adhere to medication directions. Never stop treatment early as this could increase a parasites immunity.
If your betta fish lives in solitude you may opt to treat them in their existing tank. If they live in a community tank, have carbon filters, or sensitive plants, you should quarantine them for disease treatment in a separate hospital tank.
Betta Disease Pictures and Synopsis
Some betta diseases can be treated easily, while others may have gloomier prognoses. Check your betta daily for anything abnormal. During feedings and tank cleanings is a great time to look for common symptoms of an ill betta.
Learn your fish’s personality too! Doing so allows you to quickly identify when they’re acting strangely.
Columnaris (Cotton Wool or Mouth Fungus)
Both beneficial and harmful (Columnaris) bacteria is present in your betta’s water. 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 in Columnaris. Accelerated symptoms may also include visible lesions and gill damage.
Dropsy can be caused by numerous issues including viral disease, parasites, poor nutrition, and bacteria. It’s also common amongst keepers who feed their betta’s live food.
Dropsy is actually 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.
The bacteria that triggered internal issues is contagious and can harm other community tank members. Another symptom of dropsy is the tendency for betta fish to stay close to the surface to easily get oxygen. Their appetite will also be virtually non-existent.
Fin rot or tail rot (melt) is probably the most common betta fish disease. It’s often confused with tail biting, resulting from boredom, and tears on sharp tank decor.
Upon inspection, the tail (caudal) or other fins will show visible signs of the disease. These signs include red or black tattered, sometimes bloody, edges along the affected areas and can lead to body rot if not treated.
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
Usually caused by improper nutrition or habitat cleanliness, early signs of hole in the head disease include small sores, dents, or pin-holes on the surface of the betta’s head and above its eyes. Over time these holes become increasingly larger lesions.
These cavities are easily visible and tend to travel along the lateral line of the betta. If diagnosed early, it can be cured like most betta fish diseases, but in later stages, it becomes increasingly deadly.
Another one of the most common betta fish diseases is Ich, and it’s caused by parasites. Ich is characterized by small white dots that are similar in size to a granule of sugar. These spots are 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 a betta fish’s eye and will cause one or both to bulge outwards. It can be very startling seeing these symptoms, but it is treatable. The most common cause of popeye is prolonged exposure to poor water quality.
If you monitor the quality of your betta’s water and don’t feed him or her live food, you should never experience it. Popeye on its own can be cured without long-term damage or loss of sight, but sometimes it’s a sign of tuberculosis. Tuberculosis is a more serious and always fatal betta disease.
Septicemia (Red Streaks)
This rare disease affects betta fish who are stressed (e.g. continual and quick changes in water temperature) or have been wounded. Septicemia is a bacterial infection that can be caused by adding new community fish without quarantining them, or feeding infected food.
It’s not contagious and can be diagnosed by visible red streaks or bloody marks along the body. High levels of nitrites, causing nitrite poisoning, can also lead to red stripes. Rule this out first by conducting a water test.
Septicemia may also develop alongside popeye. If left untreated, this disease could lead to organ failure and dropsy. Also note that septicemia is virtually impossible to detect on red-colored betta fish.
Swim Bladder Disorder (SBD)
The swim bladder is located 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 represent an over-estimation.
SBD is not contagious and usually clears up on its own – unless it’s a birth defect. 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, laying on the bottom, and the inability to swim horizontally.
Velvet is a parasitic betta fish disease that causes a goldish-yellow or rust-like sprinkling of color on the betta’s body, gills, fins – or all three. It’s hard to diagnose and is best identified using a light source, like a flashlight, and shining it on the betta.
Some betta fish exhibit marbling and unique coloring, so make sure you rule that out first. Betta fish are known to change colors over time as well. Bettas with velvet will 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, Velvet can lead to death.
Velvet is highly contagious to other community fish too, especially in sororities. Treat community tanks even if the other fish appear to be healthy and without signs of the disease (better safe than sorry). Velvet is caused by ongoing stressors, poor water conditions, and prolonged exposure to colder than tropical water temperatures.
Other Betta Ailments
It’s dangerous to administer medication to an otherwise healthy betta fish. If your betta fish is exhibiting any of the symptoms below, it’s not necessarily because they are sick or have a disease.
|Constipation||Overfeeding, lack of fiber in diet.||Fasting 2-3 days, feeding a pea, high-quality betta food.|
|Lethargic||Cold water, high pH, nitrate, nitrite levels, stress, sickness.||Tropical water temperature of 76-81 Fahrenheit, water changes, hiding spaces.|
|No Appetite||Not hungry, cold water, old age, stress or sickness.||Proper feeding quantity and schedule. Identify potential sickness or disease.|
|Tail Biting||Boredom||Encourage flaring, add more plants or decor, and consider betta fish toys.|
Prevent Betta Diseases Before They Start
This page outlines the most common betta fish diseases and sicknesses you may encounter as a hobbyist. It is not an exhaustive list of all potential diseases. The best way to deal with diseases and illnesses is to not get them in the first place. Be proactive instead of reactive.
Quick identification and treatment will ensure you’re providing the best care and chances for overcoming the problem. Healthy bettas are active, aggressive, and have big appetites. Sick betta fish are the exact opposite.
It’s your responsibility to learn how to care for and provide a suitable habitat for your betta fish. With that said, diseases amongst betta fish can and do happen somewhat frequently. As betta’s get older their immune systems weaken, making them even more susceptible to sickness and disease.
If you still have a question, please post it in the comments section below.