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For many years Betta fish have been one of the most popular fish in the freshwater tropical fish keeping hobby. Bettas are colorful, personable, and hardy, making them an ideal choice for new and experienced fishkeepers alike.
Even a fish as hardy as a Betta can occasionally succumb to illness, and a Betta swimming upside down can be a sign something is wrong. In this article, I consider what the problem could be and how to resolve it.
If a Betta is swimming upsidedown, the most likely cause is a swim bladder issue. When a Betta has a problem with its swim bladder they struggle to stay upright and often swim either on their side or upsidedown.
Why Is My Betta Swimming Upsidedown?
The most likely reason a Betta is swimming upsidedown is due to an issue with their swim bladder. The swim bladder’s job is to keep a fish neutrally buoyant in the water so they don’t have to expel energy just trying to stay upright.
When a Betta has a problem with its swim bladder it may end up swimming vertically, swimming upsidedown, or just rolling around uncontrollably in the water.
What is a Swim Bladder?
The swim bladder is a gas-filled internal organ found in almost all freshwater fish. The swim bladder’s job is to help keep the fish upright and neutrally buoyant in the water so the fish doesn’t have to expel energy swimming to keep still.
A Bettas swim bladder will naturally expand and contract to allow the Betta to effortlessly control its position in the water. Essentially, a swim bladder allows a Betta to ‘balance’ in the water.
When a Betta fish has a problem with its swim bladder they are often described as having Swim bladder Disorder.
What is Swim Bladder Disorder?
Swim bladder disorder, which is also sometimes called swim bladder disease or flip-over, is essentially a problem whereby the fish’s swim bladder is either damaged and deflates or moves within the fish’s body.
Fish have evolved with their swim bladder in a location that is specific to that individual fish. If the swim bladders position moves, even slightly, the consequences can be catastrophic for the fish.
What Causes Swim Bladder Disorder?
There are three main potential causes of a swim bladder disorder. These are;
In my experience, constipation is probably the leading cause of swim bladder disorder in Betta fish. Bettas are well known for their greedy disposition and they will readily overeat when allowed to. Eating large quantities of food in a single sitting can cause a Betta to become constipated.
I have had countless Betta fish in my fish room that would literally eat until they exploded if I allowed them to. No matter how much food I added to their tank, they would just keep eating it.
If a Betta becomes constipated, they may continue to eat. In fact, the first you might know of their constipation is when swim bladder disorder becomes apparent.
Another leading cause of constipation in Betta fish is cheap or poor-quality food. Cheap food is often cheap because it has been made with a large number of fillers. Fillers are anything that can be added to fish food without providing the fish with any nutritional value.
When a Betta becomes constipated there are two potential problems that can cause swim bladder disorder.
Firstly, if a Betta is constipated, but continues eating, they can consume so much food that their over-full intestines actually move their swimbladder slightly. Even this slight move can disrupt the swim bladders’ usual function.
Secondly, when a Betta is constipated for a long time, the food inside its intestines starts to rot rather than be digested. When it rots, gases are given off and these gases cause the intensities to swell, once again moving the swim bladder.
What are the Symptoms of Constipation in a Betta?
Diagnosing constipation in a Betta can be tricky. The early signs can be hard to spot, and once it becomes obvious what the problem is, the Betta could be in real trouble. The main symptoms of constipation in a Betta fish are;
Stringy White Poop
A Betta having stringy white poop is a classic sign of either constipation or internal parasites.
When a Betta has stringy white poop, it will often look like white or clear yarn hanging from the Bettas vent. Sometimes there will be small pockets of air, creating what looks like a string of pearls.
Stringy white poop isn’t always a sign of constipation. Stress, internal parasites, poor water quality, or a low-quality diet can all cause a Betta to have stringy white poop.
The first time you see the white poop, take a few minutes to look if your Betta is displaying any other symptoms that can help you pinpoint the cause of the stringy white poop.
Refusing to eat
As we have already discussed, Bettas are greedy. They will literally keep eating until they explode if you allow them to. A Betta that is refusing to eat is a Betta that is telling you something is wrong.
Once again, refusing to eat is not a certain sign a Betta has constipation, but it is a sure sign he is feeling unwell.
Spitting out their food.
Betta fish are not always the most gracious of eaters, and sometimes they will take their food in, then spit it out, then repeat until they finally eat it.
Occasionally however a Betta may take the food in, then spit it out and move on. If they are doing this repeatedly and never actually consuming any food, it may be because they full and constipated and can not physically eat any more food.
In my experience, a swollen belly on a Betta is a classic sign of constipation. Whilst internal parasites like tapeworms can also cause a Bettas belly to swell, the most likely reason is constipation.
When a swollen abdomen is seen in conjunction with some of the other symptoms above, constipation becomes the most likely explanation.
Lethargic or refusing to swim
Betta fish with constipation feel incredibly sluggish and may well just sit or even lay on the bottom of the tank. Again, this is a classic sign the Betta is suffering from constipation.
How to treat a Betta with constipation?
Over the years I have had to treat constipation in a number of fish. From small Bettas to full-grown Oscars, the process is the same. There are two ways I have found to treat constipation.
The first method, which will only work if the Betta is still eating, is to feed the Betta a high-fiber diet. Unlike goldfish, Bettas won’t eat roughage like peas, so a meaty alternative has to be found. Luckily, both daphnia and brine shrimp have a natural laxative effect on Bettas.
Both daphnia and brine shrimp, which can be fed either live or frozen, have shells, and these shells help to cure and prevent constipation.
The second method is to place the Betta in an Epsom salt bath. Epsom salts or magnesium sulfate is a white, crystal that looks a lot like regular salt. I usually just order these Epsom salts from Amazon.com.
Epsom salts are a natural muscle relaxant, and when a Betta is placed in water with Epsom salts dissolved into it, they completely relax. Once relaxed the Betta often passes the blockage that is causing constipation in the first place.
Once a Betta has passed their constipation there is a good chance their internal organs, including their swim bladder, will return to their original positions, and the Betta will be able to swim up the right way once again.
2. Physical damage
If a Betta has lost control of its ability to swim thanks to damage to its swim bladder, the prognosis is less favorable.
In the wild, there are predator fish that use damaging the swim bladder as a way to immobilize their prey. Strong, fast-swimming predator fish will swim directly into the side of another fish, hitting them as hard as they can with the aim being to damage or puncture the preys swim bladder. Once this damage has occurred the prey fish is much easier for the predator to catch.
Whilst our Bettas are unlikely to come into contact with such a predator, there is still the possibility the betta can damage or puncture their swim bladder another way. Rough handling by the fish keeper when netting the Betta is a classic reason for a Bettas punctured swim bladder.
Sadly, there isn’t a great deal that can be done for a Betta with a badly damaged or punctured swim bladder. The best you can do is either make the Betta comfortable or consider euthanizing the fish.
3. Internal parasites
In many species of fish, especially wild-caught species, an internal parasite can be a real problem. Many fish are either imported with them or catch them at a wholesale facility.
Bettas, on the other hand, are affected by internal parasites less often, Firstly, they are not wild caught (assuming they are Betta splendens of course), and secondly, the majority of Bettas are raised, shipped, and sold in cups. They hardly ever come into contact with another fish, and so there are fewer opportunities for them to pick up internal parasites.
If a Betta is suffering from internal parasites, the parasite may cause organs to swell or fluids to collect in the body cavity. These fluids can in turn move the swim bladder, leading to the Betta swimming upside down.
By far the best way I have found to treat a Betta for internal parasites is to use Paracleanse which is made by Fritz.
How to Prevent Swim Bladder Disorder?
As with just about every pest, disease, and disorder, prevention is better than cure. If you can stop your Betta from having swim bladder issues in the first place, there will be no need to try and cure the problem.
Preventing constipaion in a Betta
I have learned over the years that Betta fish need roughage to prevent constipation. For fish like Goldfish, supplying roughage is easy because I just give them crushed peas once a week, but Betta fish won’t eat peas.
For Bettas, the best way to prevent constipation is to feed them live or frozen daphnia or brine shrimp. Daphnia and brine shrimp are both aquatic crustaceans, and it is their shells that provide the Betta with the laxative effect.
Two or three times a week I give all my Betta fish either live or frozen daphnia. I give them brine shrimp less often, but only because I do not have a good local supply.
Adding either daphnia or brine shrimp to a Bettas diet keeps them going to the bathroom regularly and gives them nutrients that might otherwise be missing from their diets.
Avoiding damaging or puncturing a Bettas swim bladder
I don’t think many of us are keeping our Bettas with fast-swimming hardcore predators that specialize in ramming their prey to disable it. However, there may be occasions we all handle our Bettas a little more roughly than we should.
If you have cause to net out or handle your Betta, always do so with the utmost care. Once their swim bladder is damaged, there will be very little you can do about it.
Preventing Bettas catching internal parasites
As mentioned above, the chances of purchasing a Betta with internal parasites are small, but not impossible. The best way to prevent those internal parasites from spreading to other fish, or another fish spreading the parasites to your Betta, is to quarantine all new fish.
Placing every new fish into a quarantine tank and treating them for internal parasites, whether they have them or not, is your first line of defense against internal parasites causing your Betta swim bladder issues.
In my fish room I have three quarantine tanks, and every fish, no matter what the source, goes into quarantine for at least 2 weeks. During that 2 week period, I treat every fish for internal parasites as well as Ich, bacterial infections, and other spreadable diseases.
The most common cause of a Betta swimming upside down is swim bladder issues. Sometimes these issues can be resolved, and other times they sadly can’t.
If your Betta is swimming upside down, take the time to try and work out why then build a plan to cure the problem from there.