Common Betta Fish Disease Symptoms (Lethargic, Sluggish)

Sluggish betta fish
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Last Updated: May 26, 2022 by Dave Gibbins

Is my betta fish ill?

Nearly every betta fish owner knows the telltale signs of common diseases that affect this species. Groups of white spots usually indicate Ich; symptoms like dropsy are likely to show up as swellings on the body due to fluid retention, and fins melting away from your betta are a sure sign of fin rot.

But what about the symptoms that most sources don’t tell you? 
What do you do when you see symptoms that aren’t listed in most hobby books on bettas?

Here are some conditions you should watch for that can indicate that your betta fish are feeling “under the weather.”

Sluggishness or Lethargy

Common Betta Fish Disease Symptoms -

My betta fish is not moving around as much as normal

This symptom typically requires you to know your betta’s normal movements and habits. Bettas aren’t lazy fish; they are usually exploring the tank and playing around during the day, and very quiet and hardly moving at all when they’re asleep the whole night.

If an active betta fish suddenly becomes sluggish, it’s a sign that something’s wrong. If this happens during the first few days of acquiring the betta, then the quality of water is the prime suspect in the case. The condition may be caused by other agents, but if frequent water changes don’t eliminate the problem, further research is needed. Test the pH levels of the water – bettas do well in low to neutral pH water so if your water pH is high, that could be the problem.

Loss of Appetite

My betta fish isn’t eating his food

Many fish owners tend to think that loss of appetite is a minor concern that will go away on its own. This couldn’t be further from the truth. A fish will eat when it is sick if only to build up its energy. When a fish stops eating, that means it is conserving the energy to fight the disease – at the cost of eating and digesting food. Ideally, you should have spotted other symptoms before they stop eating but when they do, it’s time to take a closer look.

Clamped Fins

My betta fish’s fins are closed together

Bettas usually love to show off their beautiful fins, especially when they can see their own reflections or when there are other bettas around. Although they don’t fan out their fins all the time, if they constantly keep them tight against the body, then it’s an indication that something is amiss. It could be the water temperature so make sure that it’s in the neighbourhood of 80 F. If adjusting the water temperature does not solve the problem, check the pH level. Sudden and high pH levels can also cause this condition. Clamped fins don’t have a cure in themselves but they could be indicative of something bigger, like a velvet disease in betta.

Most betta conditions arise from the wrong type or temperature of water as well as poor water quality. High chlorine content, high pH or low temperatures may be causing some of the symptoms as well. Contaminants such as nitrates or ammonia could also be the culprits for these symptoms. In every case, eliminate the possibilities and then consult with an expert if none of your actions prove helpful. Bettas typically live for three to four years but if they are taken care of, they can easily live longer.

The below video has some really interesting information about clamped fins and how you can treat them:


Adam Short is the proud owner of Betta Fish Center, an educational betta fish care resource for betta owners looking for information on how to keep their fish happy and healthy. The site includes free articles, videos, user-submitted gallery images, and a betta forum where members can interact and ask questions.

What symptoms and cures have you experienced with your betta fish? Help out other betta fish owners by sharing your knowledge in the comment section.

 Thanks, Adam for your blog! Remember, there is a lot of helpful information out here on the internet, but we must recommend that sick betta fish should be taken to a vet. 🙂

16 thoughts on “Common Betta Fish Disease Symptoms (Lethargic, Sluggish)”

  1. My female betta Jewel had ick/ich and I cured her by heating up her water and adding salt for freashwater fish. She died last week because she ate her eggs. 🙁

    1. i am so sorry that really must be saddening but one question how she die if she ate her eggs. arent bettas carnoivores so they can eat meat?

  2. my george is going on four years old. I just noticed that he has a brown spot on one of the tips of his fins. It almost looks like a piece of his food stuck on it, but it is stuck… what is this and how do I treat it with a home remeady?

  3. My grandsons Betta is satying at the top of his tank and while he can swim to bottom, he cannot seem to stay.

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