How to Treat Betta Fish Swim Bladder Disease or Disorder (SBD)

Many beginner fish keepers have felt the shock of approaching their aquarium, only to see one of their fish floating upside down or swimming sideways.

Your first reaction might be to think your fish is dead or getting close to it, but on closer inspection, you’ll hopefully see this isn’t the case.

Anyone who’s seen it before will know what’s going on: Betta fish swim bladder disease.

An orange betta fish in a tank decorated with pebbles and artificial plants

While it sounds serious, swim bladder disease – or SBD -is extremely common in betta fish and, in many cases, is easily remedied.

This article will cover all you need to know about betta swim bladder disease, what to do if it happens to your fish, and how to prevent it.

What is Swim Bladder Disease?

Despite the name, it isn’t actually a disease. More accurately, it’s a generic term for a range of issues with the swim bladder of a fish. Often, it’s a symptom of an underlying condition, rather than a standalone problem.

To understand the issue, you first need to know more about the swim bladder.

Betta, along with most other bony fish, have a gas-filled organ inside them called a swim bladder. Its purpose is to control a fish’s level of buoyancy, allowing them to easily move up and down in the water, staying afloat wherever they are.

However, when a betta has SBD, the organ is malfunctioning, so the fish is no longer able to easily move around in their tank.

What are the Signs of Betta Fish Swim Bladder Disease?

If you notice any of these signs, your betta probably has SBD.

  • Your betta fish swimming upside down
  • Floating right at the top of the tank
  • Sinking down to the bottom of the tank
  • Swimming upside down
  • Developing an S-shaped spine

What Causes Swim Bladder Disease in Betta?

There are a number of causes of SBD in betta. Let’s look at the most common.

  • Constipation: This is the most common cause. Not soaking dry pellets and freeze-dried food can be the culprit as they expand within the stomach.
  • Overfeeding: Most people will identify with feeling exceptionally bloated after a heavy meal, but for betta, this can cause issues with their swim bladder.
  • Injury: A betta that has suffered an injury could have damaged their swim bladder.
  • Bacterial infection: Some types of bacterial infection can cause SBD.
  • Birth defect: Some betta with swim bladder problems are just born that way.
  • Poor water quality: High nitrate levels have been known to lead to swim bladder disorder.

Can Swim Bladder Disorder Spread?

Swim bladder disorder itself is not contagious, but the cause of it can be.

If the SBD is caused by a bacterial infection or parasites, then this can spread to other fish. If it’s due to constipation or a genetic disorder, then no it cannot.

In all cases, swift treatment is recommended, despite what the cause may be.

How Can You Identify the Cause of Your Betta’s SBD?

To treat swim bladder disorder, you first need to know what’s causing it and it can be tough to identify, sometimes requiring a bit of trial and error.

That said, we do have some tips to help you uncover the underlying cause. First of all, you must make sure your overall care of your betta is up to scratch, then work through the following checks.

The most common cause of swim bladder disorder in betta is constipation. If they are suffering from this, they’ll look fairly healthy overall, but you’ll notice a lack of defecation and a bloated stomach.

The signs of overfeeding are similar to the symptoms of constipation, so it can be tough to tell the two apart. And, constipation may be caused by overfeeding, anyway, so the two are linked.

If the SBD is down to an injury, it’s likely you’ll see some external damage. Signs to look out for that would indicate a bacterial infection include dull coloring, general lethargy and a refusal to eat.

If poor water quality is the cause, then it’s important to do a water change to remove the chemicals from the water,t hen establish a good water care routine going forward, including frequent use of a water parameter test kit and frequent partial water changes.

Finally, if a birth defect is the cause, it’s likely that your betta will have always had this issue, so if you’ve ever known them to swim normally, it’s probably not a birth defect.

Is Swim Bladder Disease Fatal?

Generally speaking, it’s not fatal, no. But it certainly can be, particularly if left untreated.

The main thing to keep in mind is that SBD is usually an outward sign of another issue affecting your fish, from digestive issues, to bacterial infection. The underlying cause must be treated, otherwise it can lead to fatality.

However, very often it can be cured.

Do Bettas Recover From Swim Bladder Disorder?

Sadly, SBD is a very common ailment in betta fish. Luckily, it’s rarely fatal.

Most commonly, SBD is due to digestive problems, constipation being the main culprit. If this turns out ot be the cause, then it’s very easily treatable as we shall discuss below.

If, however, the SBD is due to a bacterial infection, is genetic in nature or due to permanent damage to the swim bladder, then it can be permanent I’m afraid. However, even in these cases it’s not common to be fatal, and many fish can still live long lives with some degree SBD.

How Do You Treat Swim Bladder Disease in Betta Fish?

No matter the cause, the first thing to do for swim bladder treatment – if possible – is to move them to a smaller hospital tank.

It should be adequately heated, filtered and treated like your main aquarium, but with a bare bottom. This helps to remove any potential environmental issues in your main tank, but also helps confine your betta, so they don’t get exhausted trying to swim too much.

Once in the hospital tank, you should treat your betta according to what’s causing their SBD. If you’re unsure of the cause, start at the top of the list and work your way down.


The first step to treating constipation is to fast your fish for 1 to 3 days. This means no feeding at all. Often the blockage will clear out on its own, and the swim bladder disorder will disappear.

If your fish still hasn’t righted themselves in the water after their fast, try feeding either a small portion of daphnia – which acts as a laxative – or a quarter of a blanched, frozen pea – which is mostly indigestible to a betta fish and may help to clear their system out. Feeding boiled, shelled peas is a well known and common way to clear constipation in many fish.

There’s also some evidence to suggest Epsom salts can help. Add one tablespoon of Epsom salts to the aquarium for every 5 gallons of water.


The only way to cure swim bladder disorder caused by overfeeding is to fast your betta until they start swimming normally again, but for no more than three days. If caused by overfeeding, it will often go away in just a few hours.

If you’ve fasted them for three days and they still aren’t back to normal, overfeeding probably isn’t the cause.

Bacterial Infection

If suffering from a bacterial infection, they will need to be medicated with antibiotics. Try treatments like Seachem Kanaplex or API Sulfa for an external infection. For an internal infection, you’ll need medicated food or to soak your betta’s food in medication yourself.

Remember to remove any carbon filters from your aquarium before medicating, as they’ll filter out the medication.

If in doubt about how to treat bacterial infections, consult a veterinarian with expertise in pet fish, or failing that a knowledgeable staff member at a reputable local fish store.


Sometimes swim bladder disorder caused by an injury will get better with time, but sometimes the damage will sadly be permanent.

The good news is, SBD isn’t painful or fatal on its own, so you can make modifications to keep your fish happy. More on that below!

Birth Defect

There’s no cure for a swim bladder issue caused by a birth defect. However, like an injured betta, it’s possible to keep them happy in a suitable environment.

How Can You Care for a Betta with Chronic SBD?

Just because a betta has chronic swim bladder disease due to an injury or birth defect, it doesn’t mean they can’t live a full and happy life, it just means you must tailor their environment to fit their needs.

A wide, shallow tank is best as they don’t have to do so much work to swim to the top for air, or to the bottom for any food that may have settled there.

It’s also advisable to place live or silk plants with wide, flat leaves in their tank, as they can rest on them when necessary. You can also buy “betta hammocks” which serve the same purpose.

Is There a Way to Prevent Swim Bladder Disease?

There’s no 100 percent effective way of preventing it, but there are several things you can do that will significantly decrease the chances of having issues.

  • Never overfeed and ideally feed two smaller meals a day rather than a single larger one.
  • Don’t feed freeze dried foods or dried pellets unless you soak them in a little tank water before feeding, as they’ll expand in this time instead of expanding in the stomach.
  • If you need to net or handle your betta, be extremely gentle to avoid injury.
  • Make sure the tank contains clean water with appropriate filtration and cycling in place.
  • Keep an eye on water parameters and temperature.


Swim bladder disease might look serious, but in most cases, it’s nothing more than the result of your betta overeating.

That said, it certainly shouldn’t be ignored, because she can be a sign of something more serious.

This post has given you all the information you need to treat and prevent betta swim bladder disease, so now you’ll know what to do should you start to see the signs.

B Hamilton

Hey there! I'm Brian, a lifelong enthusiast and fish keeper with a wealth of knowledge and experience on freshwater aquariums, that I love to share on this site. If you have any questions or need any help, please do ask in the comments section below, I'd love to hear from you and will help where I can.

27 thoughts on “How to Treat Betta Fish Swim Bladder Disease or Disorder (SBD)”

  1. Avatar

    Hello. I’ve had my betta, Maximus, for only a year, but there is no way of knowing how old he actually is. What I’m seeing might be old age, however, if it’s SBD then I need to treat it. He was in a ten gallon tank with filter and heater and I’d kept the water quality monitored. About two months ago he suddenly (over the course of an afternoon) went transparent. (he’s a Paradise male with dark body and yellow fins.). His fins were already frayed, but they started to disappear and he became lethargic. At the advice from a local fish-aquarium store, I dosed the tank with bettafix and fed him food soaked in Seachem’s Metroplex and Focus. He got most of his energy back, but not his fins. I can’t see evidence of fin rot, but it doesn’t mean it’s not there. Either way, the fin loss stopped, but he never grew anything back. Then a few weeks ago he started some heavy-duty sleeping. I’d thought that perhaps it’ was old age and his little body was winding down. We placed him in a much smaller tank, but the water is about 6 inches deep because we don’t know how to utilize the filter and heater with less water. From previous attempts at feeding, I thought he was uninterested in food, which is what an animal does when it’s dying. He stopped swimming to the surface and now lies on the silicone anemones lining the tank bottom. Just to be certain about his appetite, not wanting to starve him, I dropped some blood worms in via a dropper. The next day I couldn’t see them. I wasn’t sure if he’d eaten them or they’d somehow dissolved. So today, before leaving the house, I’d dropped in a few more. When I came back I caught him moving and jumping at something on his anemone. I think he’d found a bloodworm and was eating it. So, thinking about how he stays on the bottom now, I wondered if what I was seeing was old age coupled with SBD and NOT a case of the grim reaper. I went online and found your article/blog … (btw, it’s one of the most informative I’ve discovered so far. Keep up the good work!). I read the part you’d said about the ‘S’ curve in the fish’s posture. I’d noticed that Maximus is sway-backed now. I don’t see him swimming, so it may be only when he rests, but it’s definitely there and not how he used to be when he seemed fine. Is this the ‘S’ curve you spoke about? Anyway, I was hoping for some expert help with my little guy. Any suggestions or observations or questions would be welcome. Thank you! Thea

    • Wendy Kathryn
      Wendy Kathryn

      Hi Thea,

      Loss of colour can be any number of things, from internal parasites, a bacterial infection, or – most commonly – poor water quality (high ammonia has a bleaching effect). It can also sometimes even be natural, particularly in marbled types of betta, although that doesn’t apply to yours from the description.

      Are you monitoring water quality in the tank?

      I recommend taking a read of our ‘betta disease guide’, where there’s tons of useful information: Betta disease guide

      I would also suggest if you can, joining a couple of forums, taking pictures of your fish from many angles, and making a post to get many peoples opinions. There’s some real experts on there who can offer great advice, and it’s a good way to get the opinions of a few people, many of whom are breeders and far more knowledgeable than I: forum
      Bettafishcenter forum

      I hope you can get your bettas health sorted.

  2. Avatar
    Elaine Broacha

    Hi,My name is Elaine and I have a male betta with a lump on his left side where hi swim bladder should be. He is having trouble swimming upright, normally laying on his left side on the top of the water. He is in a 2 1/2 gal tank that is filtered and 50% water changes every 3 or 4 days, His color is good, he has a great appetite. I have tried fasting him for 4 days, Tried the epsom salt dip,Tried the peas, nothing so far has worked, H has had this lump and condition for about a month and a half, before that he was fine. I don’t think I was overfeeding , as he gets 2 or 3 pellets a day and some bloodworms or daphnia once a day. Can you think of anything else I could try? He’s such a fighter, I don’t want to give up on him.

    • Wendy Kathryn
      Wendy Kathryn

      Hi Elaine,

      It’s very hard to diagnose betta illness because unless it’s something strikingly obvious, it’s hard to know exactly what may be happening. I usually just go through a list such as the above, a process of elimination, and hope to have some idea at the end. If not,t hen a good thing to do I find is google ‘betta fish forum’, take a few pictures of my fish from different angles, and post in there asking for advice from many people all at once. There are some incredibly knowledgeable people in the forums, many breeders and lifelong collectors, who have pretty much ‘seen it all’ and can be a fantastic source of help.

  3. Avatar
    Arlene Franklin

    Hi, my name is Arlene and I have a male crowntail betta. He was in a heated and filtered 6.5 gallon. I am trying now to fast him for a few days to see if that helps but he just seems to be getting worse and I don’t know if I should try something different instead of not doing anything for 3 days. He is blue but he lost his coloration and his fins have been getting worse. I’m not sure if it’s bacterial but we’ve moved him to a little bit smaller than a 1 gallon to make sure he can swim when he needs to since it’s not as strong a filter. His body is in that ‘s’ shape and he lays on the bottom of his tank without moving. I’m afraid that he will pass away if I don’t do something to try and fix his condition. I know problem solving will be best but I don’t want to hesitate to give medicine as needed. I hope to get a response as soon as possible and thanks for your time!!

    • Wendy Kathryn
      Wendy Kathryn

      Hi Arlene,

      Have you tested the water parameters? It’s very common for high nitrate in the water (nitrate poisoning) to lead to lethargy, lost interest in food and a bending of the spine (the s-shape you describe), so the first thing you need to to do is test the water parameters and make sure he’s not being poisoned. You could also put Bettafix or Betta Revive in the water, which some people have success with.

      But really, because it could be water parameters, a bacterial or parasitic infection, it is impossible for anybody to say over the internet, and you could even get wrong information leaving the true cause untreated. Only a vet or true expert could make a proper diagnosis, and only after actually seeing your fish in person in the flesh.

      Sending you best wishes, I hope he gets better!

  4. Avatar

    Hey, my name is Spencer, and I just got another Beta veil tail, named Auggie, in september. I love him, but while I was looking in his bowl I found that his water was murky, and food was at the top of his bowl, so I changed his water like I do every so often. When I placed him in his bowl, he was having trouble swimming, tilting, sinking floating, it worried me, so I ran right to the thought of SBD. I really need help, please! I have placed him in a hospital container, and I am very worried.

  5. Avatar

    I have had my male Betta for less than a year. He has been very active and social until he stopped eating 3 days ago. He is staying close to the bottom of his 5 gallon tank or hidden in the plants. He looks bloated and I have been treating it like constipation. He will not eat a pea, so I tried an epsom salt soak yesterday. The swelling is still present, with a whitish color to it. No pine cone scales and his fins look normal. I did a partial water change 2 days ago and the water tests healthy, as always. Do you know what might be going on and if there is anything further I can do to save him?

    • Wendy Kathryn
      Wendy Kathryn

      Hi Jann,

      Unfortunately, it’s incredibly hard, and almost impossible to try to diagnose any illness or disease over the internet, and I’m always a bit reluctant to do so anyhow, because if I am wrong then you may perform the wrong treatment, making me somewhat responsible. All I can do is advise to seek out professional help. Sorry.

  6. Avatar

    Hi! I really need help because I am scared for my betta. I got him back in early July, so I believe that he is fairly young. He is pretty small at only one inch and a half… he is a red butterfly double tail. Recently he has been having trouble swimming; he ‘wiggles’ in short burst to somewhat swim, then when he is at rest, he supports himself with a plant, the side of the tank or he lays at the bottom. It’s like he is top heavy. He used to be a bright red, but now he is a dark, almost brown in colour. He is eating normally, but he has almost no energy. His fins look normal except a little torn. He also has some unusual black spots on his left side and a barely noticeable lump on his right side… it scares me so much…

    • Wendy Kathryn
      Wendy Kathryn

      Hi Alex, have you tested the water parameters? This is always the first thing to check!

  7. Avatar

    I have a betta that started out with a regular swim bladder issue… floating the top, on its side. Then his entire body swelled with air under the skin that made half of his body stick out of the water. No scales pineconing but is very distended and contorted and in pain. I plan to stick a needle under the skin to releave the pressure. My question is… How did this happen?

    • Wendy Kathryn
      Wendy Kathryn

      Hi Brian,

      It’s impossible to say how it happened, as it could be due to many things, such as water parameters, illness, parasites, the possible causes are many.

      “I plan to stick a needle under the skin to relieve the pressure” – Sorry, why would you do this? This can’t be a good thing 😮

      • Avatar

        Hi. Update on the betta. I did stick a needle in at the area where the swim bladder is. Just enough to puncture between the skin and swim bladder. 20 minutes later he deflated with no air left under the skin and was able to stay upright. Being that I didn’t puncture the swim bladder, it did stay slightly inflated so he still had issues swimming. It took almost 2 months for the swim bladder to resolve itself. He did not have his body swell with air again and is now living normally. As to why I would even do such a thing, since you asked, was to save his life. So if anyone encounters this particular situation, this is how I successfully deflated the air under his entire skin. Attempt at your own discretion.

  8. Avatar
    Eileen Burns

    I’m glad I finally found someone to ask, my local pet store didn’t have anyone to talk to. My battery Mizu has been with us for almost 3 years. We found a 2.5 gallon tank with a filter that doesn’t upset him, plus we have the water baffled with a leaf hammock. The only way we have found to keep the tank heated is with an electric heater nearby, which works, we closely watch his temp. He has always had issues with fin rot it seems but that finally resolved when I added an Indian Almond leaf and used a turkey baster daily to collect waste. Well he stopped pooping around December 21 or so, so we stopped feeding him and then fed him some peas. Didn’t poop still and had also been seen laying on his side at the bottom. It then became clear shortly after that he sinks to the bottom if he’s not resting on his silk plant. I then read about doing a 3 day fast and then a pea diet, so we did that, then fasted him again for 2 more days and have fed him some peas, we can usually only get him to eat 2 to 3 pieces, with garlic juice on them, but he has such trouble feeding now we basically have to place the pieces on our dinner and put above his mouth. Also, there is some coloring around his eyes, maybe due to swelling? His eyes don’t look cloudy otherwise. No scales sticking up. He has pooped for us twice, once on 12/24 and once a few days ago but he usually would go everyday. We feed him normally about 2-3 pellets twice a day but had cut down to no more than 5 pellets, but he could have found some at the bottom that he missed. I’m not sure if we should try Epsom salt, and/or medication, and/or change his food. Also got the water tested and everything was good, we do partial water changes weekly. We feed him premium Beta Bits made with shrimp. I’ve had to keep the filter off because the current makes it hard for him to stay on his plant. Any advice you can give would be so appreciated! Thank you

  9. Avatar

    Hey, I have a female beta rutilans named Emmaline and just today she was laying at the bottom of the tank un-responsive to my usual greeting of a poking the water (she is playful and zooms around the tank kinda like hide and seek), she wasn´t sleeping because she usually sleeps beside the heater In her tank and now when she does try to swim she struggles to stay up right. I heard about SBD and I usually feed her once a day before bedtime so i dont over feed her. I cleaned her tank this morning and she was perfectly fine…what do I do?

    • Wendy Kathryn
      Wendy Kathryn

      Make sure all water parameters are good, most problems start there. Also try fasting her for a day to see if it’s anything digestive system related.

  10. Avatar

    Hi there. My crowntail tikki gets swb every time I feed him. It lasts for a day or two or three then goes away. I feed him once every 3 days and once he eats again it comes back. I keep his water warm and clean, Indian almond leaf is in there and so is a tiny bit of pimafix. This time he is not pulling through. I want to feed him cause I dont want him to starve but hes not getting better. By the way I feed him frozen but thawed blood worms, dapnia and brine shrimp. Never dry food and I try to feed him under the water so hes not gulping air. Please help. I love him.

    • Wendy Kathryn
      Wendy Kathryn

      Hi Melanie,

      So sorry to hear this 🙁

      If your water parameters are correct, then it sounds like you’re doing all the right things to try and help. It may not be SBD, it could be another illness, or something parasitic, or maybe old age or even a (natural) general decline in health. It’s impossible to say I’m afraid 🙁

      You might have to consult a veterinarian that specialises in fish.

  11. Avatar

    I’ve had a rescue betta for over year now and I’ve had to fix many health issues with this guy. I’ve helped him with constipation before but this time something is different. He is sinking to the bottom of the tank and has a hard time reaching the top. I’m pretty sure he has swim bladder disease. I want to get started on treatment right away because I know he is uncomfortable. I’ve read many articles about how to help but there is just one thing I can’t seem to find advise about. The heater and filter I have have a minimum water level so it can work properly. But I need to have the water level lower so he can reach the top for oxygen. How am I supposed to heat and filter my tank like normal but have the water low enough? I can’t just go out and buy new tank equipment. What should I do?

    • Wendy Kathryn
      Wendy Kathryn

      Hi Abby,

      Although betta are ‘labyrinth fish’ and can take oxygen from the surface, they are also just like other fish in the way they have gills and take oxygen from the water…so long as the water is oxygenated enough, which is your filter is causing disturbance at the surface then it should be.

      You could try adding some plants (real or fake…if fake, then soft ones only with no sharp edges to protect yuour bettas fins!) or you could add an ornament or two, which could offer a platform / resting place higher up in the water column for your betta to rest on and be closer to the surface.

  12. Avatar
    Jaxon Vandal

    So I just got my Betta. And I don’t know anything about fish, but I decided I should try and get one. I got him yesterday. And well I bought Frankie. And he doesn’t swim around the tank he just lays at the bottom of the tank. He does come up for food and occasionally up and around. My roommate saw him and told me that he probably has a swim bladder problem. What do I do? Also I noticed his spine is like an S.

    • Wendy Kathryn
      Wendy Kathryn

      Hi Jaxon,

      Please read and follow the advice in the article above 🙂

  13. Avatar

    My Betta, Leon, recently stopped eating and just sort of floats at the bottom of his tank. He refused to eat anything, and he hasn’t eaten anything for about 4 days. I tried feeding him boiled peas soaked in water, but he doesn’t want to eat it. What should I do?

  14. Avatar

    Iam scared as heck!My betta never swam this way, it is twitching and shaking while being on the top of the tank. I cleaned its tank before this happens, and the water is warm. But I dont have a filter nor a heater. Iam scared that it will die,will it? and will it stay for long or not what should i do…..PLEASE ANSWER FAST

  15. Avatar

    Hi, I just got a male Betta about 3 or 4 days ago. When I got him he was in one of those small containers that all the Bettas come in. He seemed to be fine and happy. However, I put him in his tank later that day and I noticed over the next couple days that he is just staying at the top of the tank. He seems to still be very healthy… He isn’t losing any coloring and isn’t lethargic. His only symptom is that he bobs/floats at the top of the tank but he still remains pretty energetic. Two days ago I gave him a pea and for the last day I have fasted him ( I plan on fasting him for 3 days and if that doesn’t work I will give him a salt bath and if he still isn’t better I am going to give him some more peas). Since starting to treat him he seems to be able to swim to the bottom of the tank a little easier (at the beginning it was really hard for him to do this) and he will wedge himself between the tank and a plant. Since he is new from the pet store I am wondering if they overfed him there or I do feed him flakes (but I have fed all of my past Bettas this and it has not affected them however I will if need be soak the flakes). Either way I feel very bad for him and want to help… Does anyone have any idea what the issue is and what I should do to cure him? Thanks!

  16. Avatar

    We have had our Betta for over 2 years now. About 2 months ago I noticed what appeared to be fin rot, and the next month he seemed to have lost his floating ability. He started laying at the bottom of the tank on his side, or against something, but with his head up watching us. I treated him for a bacterial infection, and he got some of his spunk back, but still has no “float” to him. Immediately sinks. He still eats, swims normally when going to the surface, but mainly lays around. He will still show interest in saying hi, and dancing a bit with me, just from the bottom of the tank. I test the water almost daily and it’s pretty good, maybe a little higher ph than I’d like (upper 7’s), but could this be a sign of old age?

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