Common Betta Fish Diseases and Symptoms

Betta fish diseases can affect bettas in a variety of ways. Betta fish illnesses are often caused by poor water conditions, stress, and improper diet.

Betta fish health problems should be addressed as soon as they arise to avoid more serious health issues. It’s always best to keep a lookout for any signs that something is wrong and get them checked out when necessary. If left untreated, many betta diseases can become fatal before too long!

In this blog post, we will discuss symptoms you need to look out for and common betta fish diseases that may be causing them.

Symptoms of disease in betta fish

It’s important to know the signs that your betta fish is sick. By getting to know the normal appearance and behavior of your fish and looking out for anything out of the ordinary, you’ll be able to spot health problems and treat them as soon as they arise.

  • Floating or swimming sideways. Your betta should look like it is in control of its swimming motion and not float upside down or on its side.
  • Resting at the bottom of the tank. Bettas do not usually rest at the bottom of the tank for extended periods of time.
  • Cloudy or red eyes. Betta’s eyes should look clear and bright. If there is any cloudiness or redness in their eyes, this can indicate an underlying issue with your betta’s health.
  • Clamped fins. Clamped fins means that your betta fish is holding its fins close to its body. Clamped fins may also be frayed.
  • Red streaks or patches on the fins or body. Red streaks can be a sign of a bacterial infection. Bacterial infections can be triggered by stress, poor water quality or even aggression from other fish.
  • White spots on the fins or body. This is likely to indicate an infestation of parasites such as ichthyophthirius multifilis (ick). These parasites will lay eggs on any available surface in your betta’s tank which makes them extremely difficult to eradicate.
  • Cotton-like growths around the mouth. Your betta may have developed columnaris. Columnaris is a bacterial infection that can be triggered by stress and poor water quality.
  • Turning white or pale in patches or all over. This could be a sign of high ammonia levels in your tank water.
  • Swollen body or a fat belly. Your betta could be suffering from dropsy, which is a potentially fatal problem. While dropsy can be treated, it’s not always easy and it’s important to act quickly.
  • Torn or ragged-looking fins. Torn fins can be caused by poor water quality or by injury. For instance, your betta may have been attacked by another betta or caught in the filter outflow.
  • Biting their own tail. Often a symptom of boredom, it’s not unusual for a betta to inflict harm on themselves by biting their own tails.
  • Swollen eyes. Possibly a sign of injury or infection.

Common Betta Fish Diseases

There are lots of potential signs of diseases in betta fish, and most are quite easy to notice, but if you do spot one of these symptoms, how do you know what is causing it?

In this section, we’ll look at the common betta fish diseases that are the most likely causes of sickness in your betta.

Swim bladder disease

Main symptoms: Floating strangely, swimming sideways or upside down, not appearing in control of swimming

Swim bladder disorder is when you’ll notice difficulty with swim movement or inability for your betta to stay at the surface of its tank or bowl because it has lost its buoyancy control due to a problem with its swim bladder.

Fin Rot

Main symptoms: Torn, ragged-looking fins

Fin rot is where the fins start falling apart at the edges, turning into ragged looking tatters. If your fish’s fins look like they have been torn or shredded then you can be sure that your betta is suffering from fin rot.

Dropsy in betta fish

Main symptoms: Weight gain followed by loss of scales and swelling around the belly area. Also lethargy and abnormal swimming behavior.

Dropsy is condition where you’ll notice your betta fish becoming swollen. Betta fish with dropsy will appear to have a large belly and their scales will stick out. Dropsy is caused by internal organ failure, usually because of bad water quality.

Ick in betta fish

Main symptoms: White spots on the fins, gills and/or body.

Ick in betta fish is caused by a parasite that attaches itself to the betta’s skin. This will cause your betta to itch and scratch constantly, which can lead to secondary infections if not treated properly.

Ick is quite easy to identify as you will notice distinctive white spots on your fish’s fins, gills or body.

Constipation in betta fish

Main symptoms: Your betta will be bloated and have a distended stomach with little appetite. You may also notice a long trail of stringy feces behind your betta.

Constipation can be caused by feeding your betta fish too much or by giving them a poorly balanced diet.

Signs of constipation in betta fish include bloating and swelling below the Betta’s stomach area.

To avoid constipation, ensure that you only feed your betta small amounts and give them a wide variety of foods.

Tail Biting

Main symptoms: Biting own tail and causing self-harm.

Tail Bitting is where the betta injures themselves by repeatedly biting their own tail. This is not due to a betta disease, but rather an abnormal behavior that can be caused by stress and boredom. Boredom may bring the betta’s attention towards their own tail because it moves in front of them while they swim around.

Neon Tetra Disease

Main symptoms: Loss of coloration, difficulty swimming, cysts that appear as lumps on the body, and the fish’s spine may become curved.

Despite the name, Neon Tetra Disease does not just affect Neon Tetras, it affects many other types of fish too, including betta fish.

Neon Tetra disease can be fatal to betta fish, but if you catch it early then there is hope for your betta.


Main symptoms: One or both eyes will be noticeably enlarged.

Pop-eye is a condition where one or both of your Betta’s eyes appear swollen. Lethargy combined with pop eye may indicate dropsy.

Velvet in betta fish

Main symptoms: Yellow or rusty color appears on the body, fish rubbing against objects, lethargy and loss of appetite.

Velvet is a betta fish ailment caused by parasites. These parasites can easily spread from one betta to another, which is why you should be particularly careful when adding a new fish to a tank.

You should also clean a tank thoroughly before adding a new fish to a tank where velvet has previously been a problem.

Betta Fish Fungal Infections

Main symptoms: A white or grey substance on the fins and body along with clamped fins. The fish may also rub against objects.

If your Betta has a fungal infection, you will need to treat it with special Betta Fish anti-fungal medication. You can find these drugs at your local pet store or online.

More Betta Fish Advice

If you found this guide to betta fish diseases useful, we recommend reading the articles below to learn even more about your betta and how to care for them properly.

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