Q: CF wrote,

Why is my betta’s stomach so bloated? Is he getting fat?

A: A few things can cause a bettas stomach to bloat. Overfeeding is the most common culprit. Most fish food containers advise you to feed your betta what they can eat in two minutes. Because bettas tend to bloat it’s better to offer him just a small amount of food at a time. A bettas stomach is about as big as one of his eyeballs so feeding about that amount twice per day is safe. For a grown male that equates to about 3 – 4 pellets, large flakes or blood worms or a couple of brine shrimp. Dry foods like Betta pellets, Bio-Gold or freeze-dried bloodworms (not to be confused with frozen) contain less then 10% moisture and swell when introduced to water. A bettas natural diet consists of live insects and insect larvae that contain nearly 90% water. Some bettas have difficulty with the dry foods and will constipate. after eating them. To avoid this potential issue, soak dry foods in a cup of tank water for about 10 minutes before feeding allowing them to swell with water before entering the betta’s digestive track.

Bloating may also be a symptom Dropsy. Dropsy is a term that describes the final stages of organ failure. Unfortunately it is very common among bettas and is nearly always fatal. Bettas that do initially overcome it often succumb to it again in the following weeks or months. Dropsy is believed to be caused by bacterial, viral and/or parasitic infections/infestations. The bloating is caused by the build up of fluids internally and is often diagnosed by the telltale “pinecone effect” or a massively bloated abdomen that appears to be filled with fluid. Click to learn more about Dropsy.

Betta in final stages of Dropsy

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Reader Interactions


  1. insane veggies says:

    oh my god! i had no idea it was so horrible. i want to cry just looking at this. is there any reaserch going on to prevent or treat this?

    • Elle says:

      I just wanted to add in- whenever I feed our betta flakes he’s great, and when I switch to the pellets (even if soaked) he bloats up. Therefore, for those you having problems- try to switch to flakes only! Works for ours!

  2. Christie says:

    I’m not aware of any specific research for fish Dropsy going on at this time but I will certainly post anything new that comes along. It’s a difficult thing to treat because Dropsy itself isn’t a disease. The bloating you see is a symptom, most likely, of the organs failing. This can be caused by any number of things, bacterial, viral, etc. The best way to avoid it is to keep your water clean and your water parameters in their safe and ideal ranges. Check back in a couple of days. I had another reader write in with another severe dropsy case and they provided photos showing the bloating concentrated just in the abdomen, which is also quite common. I will post that story soon along with the photos.

  3. Anonymous says:

    wow! we have same the same syptoms with our betta. I feel very bad since there is no cure for him. Is our betta feeling pain?

  4. Anonymous says:

    I recently got a new betta about two months ago. Since I got him, he has had a severe problem with bloating after every feeding. I have tried feeding him different types of betta flakes, soaking them first, and feeding only every couple days, but it still happens. Lately, I have been feeding him small bits of peas which he does not seem to have problems with but is this enough nutrition for him? If anyone has any ideas I would be really appreciative! Thanks!

    • nikki says:

      thats what happens to mine!!

  5. Anonymous says:

    i read that only peas alone hasnt got enough nuutrition for a betta. my fish has been bloated for a couple of months or so. he still acts normal. im going to try feeding him less, soaking his food pellets and i was also told that giving him peas once a week is beneficial.

  6. Anonymous says:

    My betta also has bloated tummy. And I think it’s due to feeding him with too dry pellets.
    Planning to keep him without food for couple of days and see for any changes.
    Do you know anything else which I can do in the meanwhile?
    Pls advice.
    Thank you.

    • anonymous says:

      you could try to soak his pellets before you give them to him. they get bigger in water so you might find you don”t have to feed him as much. he could also just be constipated and if he is, try peas.

  7. Kat says:

    I am sad to hear that my Fred will soon die. In light of that, I did aspirate his abdomen with a diabetic syringe which gave him much relief. I pulled 2.5cc out of him and it was yellowish and cloudy. He seemed to be much more comfy and is not gasping for air or aggitated. He is resting now. I love Fred and can not stand to see him suffer. I have also introduced the bettafix to comfort him. I put in a airstone so that he will not have to fight to breathe. He has been on my desk for a very long time now and sometimes I feel he is my only friend in a such a hard atmosphere! Silly, I know. I take care of strays and feed everything so this is not a surprise to anyone that I was willing to perform surgery to help him. When I die, I hope I come back to an owner like me. At least I know that I will not suffer, be afriad, or go hungry. This site helped me more than you will know. I thank you for this too. I am sure he will succumb to this again, if he makes it over this hurdle. I will be there with him every step of the way to do what I can for him. The WWW, knowledge is power. Thank you so much.

    • Kelly O'Rourke says:

      You are just like me .I’m crying reading your post. My “Hope “has this too and I have done all that you did but the aspiration. I have done it on cats but never a fish and I’m terrified too kill him .:( I’m treating with tetracycline and Ick cure and a little aquarium salt. I feel just miserable and devastated. MY home us full of rescues of all sorts too and I love them all.

  8. Anonymous says:

    I made the mastake of my fish having dropsy, but it was actually the fact that she was pregnant. She looked very fat and it looked like some pictures I saw, but there was a little white tube sticking out of where the poo would come out(sorry if that sounds a little gross)but it meant that she was spawning. So if you have a female beta that seems to have dropsy, make sure you check to see if she’s pregnant first.

    • Shylo Asay says:

      Question, so I bought a male beta, and he has that white tube sticking out. Is that normal???

    • DarkLady says:

      A female betta cannot be pregnant. During the dance the female releases the eggs into the bubble nest and the male inseminates said eggs then gaurds them. It isnt like live bearing fish.

      Please do your research.

    • Star says:

      So if she is like that what do you do?

  9. Anonymous says:

    how long does a fish with dropsy tend to live?

  10. Ani says:

    Hi everyone. I came after work today and saw that my fish is in the same condition, I thought he has that kind of stomach cause of I didnt feed him one day. But apparently its not… im going to take my pet to the pet store and ask if anyone knows what to do, I HATE THE FACT THAT IT COULD DIE. He is so beautiful…

    • Rich says:

      Try piercing your Betta’s belly with a sowing needle and gently squeeze its belly a bit. I did it to mine and by the next day he was back to normal and has been happy ever since! I can’t say what was officially wrong, but death seemed inevitable so I felt like I had nothing to lose. It also works on cows!

      • Kelly O'Rourke says:

        If my “Hope” gets worse I will be desperate enough too try that .He fought off Popeye months ago and is now sick again. I have 8 Beta’s all in separate 1.5 too 3 gallon tanks with filters and bubbles and clean water everyweek 75 %change and once a month complete change. When I read that this was due too poor quality I felt sick and responsible andv still do. All the other 7 are fine.

  11. LWoodson says:

    Our precious Betta bloated with the good freeze dried pellets. There was no going back. We tried fasting him and tiny pea pieces. Nothing worked. Since this is such a horrible problem with Bettas, I will now go to the advised feeding of meel worms (90% moisture). The freeze dried pellets are just too constipating, thus starving the fish to death. Loosing our betta ripped our hearts out.

  12. nicole says:

    I tired fasting my betta and his tummy swell did go down a bit… but whenever i feed him he bloats up even bigger!! ik my betta is male, what is it and what can i do ti hell him?!?! 🙁

  13. Lori says:

    My betta’s stomach bloated up severly, I did the pea trick thing, next day, back to normal. I didn’t feed him that day, the third day I gave him one pellet after soaking it in his tank water for 15 mins.. everything seemed fine until about 12 hours later, then he bloated up again and bobs to the top of the tank, can’t swim down and bobs on his side. I didn’t feed him for 24 hours, then did the pea thing again and the next day he was fine. Then I fed him again, one pellet, soaked until soft and 12 hours later he’s all bloated again and can’t swim. What is happening? He can’t live on one pellet every other day! What do I do? Should I switch to flakes? I tired the freeze dried bloodworms and then same thing happens even when I only give him one worm. Please help. I’ve read everything I can find on the internet and even emailed some “experts” but everyone says the same thing. I know this is no dropsy because it goes away and then come back. I know ONE pellet every other day is NOT overfeeding him.. What can I do?? I hate too see him suffer but I don’t think he can live like this and get the nutrition he needs from one pellet 3x’s a week.

  14. Hope your bettas feel betta plus I have a male elephant ear betta he has a blue tail and red fins he’s very colorful and pretty.

  15. Kayla says:

    I have a betta named Phoenix who I just got about a month ago… Before he was in a 41 FL OZ “tank” that originally was meant for two bettas as it came with a divider and two small fake plants. Just yesterday, I finally upgraded (since I’m still young and cannot drive yet, which my parents refuse to take me at some times, to a 3 gallon tank with a filter, and a LED light.
    Before, my betta fish didn’t like me. I mean, I wouldn’t like myself either if my owner put me in such a small place. But now, my betta is happy and thriving! He likes to explore around his plants that he has and likes to play with the filter. The only problem is that he is bloated.
    A week ago, my family went on a vacation in which our grandparents came over to our house. While we were gone, they basically house sitted. And fed my betta. When I came back, my betta was severely bloated. It looked like it’s head was about to pop open (or more like his stomach). What do I do? I fasted him for a day and his swelling went down a bit, but I fed him again and it went back up… And this morning I tried to feed him a pea but (to my surprise!) we didn’t have any. Is there other type of food that I could feed my poo Phoenix to help stop his bloating?

  16. Dylan says:

    The best way to avoid situations like this, put in simple terms at least. Always use a softer water, and purchase Atisons’s Betta Spa Botanic water conditioner. (Does not dechlorinate) or use almond leaf extract of some kind. Bontanic Betta Spa, has it all and will not discolor the water. Plus adds calcium and very perfect amount of sodium chloride. Helps to avoid using too much salt. Perfect solution, literally, for the average betta hobbiest.
    Yucca extract in this product also helps to temporarily bind ammonia. Thus making a smaller habitat slightly more habitable. Of course this is just one method, some hobbiest don’t believe in using salt in betta habitats. I use Betta Spa and it makes a noticeable difference in all of my betta, and I keep crowntails.

  17. Yanires says:

    My fish just started bloating today, I think. I just got her a couple of weeks ago. I also have 4 other Betta’s and they are all fine. Last night I gave them each 3 really small pellets. They were all fine and then in the morning I gave them a little sprinkle of flakes. I leave the room and then come back and see that my fish is at the top of the tank; not able to swim back down and is tilted to the side. This has never happened befor and I’m kinda nervous. I don’t have pees so I can’t feed her that. All the other fish are fine, even the one that I got on the same day as I got her. They are both the same size except ONE IS FAT and the other isn’t. I think its because of the pellets so I’m going to stop giving her so many. Hopefully that works but if it doesn’t can someone please give me advice. I REALLY NEED IT!!!

  18. Lisette says:

    Hello, I went on a trip for 3 days and I came back to a fat fish, he was constipated and i was treating with with peas, he was getting better, he had a small bumpy tummy on his side , now after the trip he got fat, out of nowhere and I don’t know what to think or expect, I check on my fish everyday he is active ,alive I haven’t feed him for a week ,am afraid he will explote I wish a can post a picture .we even got him a bigger tank.

  19. Zackarii says:

    Thank you for writing this article, I didn’t realize you could overfeed your betta fish!

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