Why Is My Betta Fish Floating To The Top And On Its Side? 10 Reasons

    betta not moving at top of tank

    It can be horrific to see our beloved Betta fish floating in a way that they’re not intended to float. When you do see that uncommon scene, you’re automatically going to ask, “Why is my Betta fish floating to the top and on its side?” Fortunately, we have answers for you.

    There are multiple reasons why your Betta fish might be acting this way, and not all of them are scary. It might be because of the temperature, the oxygen in the water, or some other factor.

    However, it could also be a symptom of a more significant issue.

    Thus, you need to know the possible reasons why your Betta might be behaving that way, and you can do that by reading this article.

    10 Reasons Why Your Betta fish Is Floating To The Top And On Its Side

    swim bladder disease betta

    There are multiple reasons why your Betta fish might be floating to the top and/or on its side.

    Fortunately, most of the reasons are not that serious.

    As a good aquarist, you need to be an expert on your pet’s behavior so that you can learn when to be cautious and what needs to be done.

    This section will talk about all the possible reasons why a Betta might act this way.

    1. The Aquarium Water May Be Too Warm

    Betta fishes are hardier than most beginner species, which means that they have a wider temperature tolerance of 75° to 80° Fahrenheit.

    However, they do still suffer from extreme changes in their water temperature, especially once it starts to approach the outer extremities of their tolerance.

    If your aquarium water is too hot, you can sometimes see Betta fishes float this way.

    This is because they’re trying to cool down by being nearer to the cold open air.

    This can typically happen during the summer months, especially if your aquarium is situated in direct sunlight.

    Betta fishes are labyrinth-breathing fishes, which means they can inhale direct air.

    This also means that they’re used to being near the surface of the aquarium, so if you think that it’s floating up and to its side because of the temperature, just let it cool off or improve its fish tank.

    2. The Aquarium Water May Be Too Cold

    The same thing happens when the water of your aquarium is too cold.

    Fish’s metabolism slows down when the water becomes very cold.

    If you’ve ever been ice fishing, you know that larger species of fish in the lake tend to congregate near the bottom of the water body and take their “winter rest.”

    During these times, fish become dormant; they move very little and don’t do much to hunt.

    Some species, like koi fish, burrow into the sediment and hibernate.

    However, Bettas are inherently not used to this type of environment, as they come from warm tropical climates.

    Even generations of breeding in non-tropical areas haven’t changed this aspect of Betta splendens.

    When it becomes too cold for your Betta fish to bear, it will also want to get closer to the heat source to warm up.

    Thus, floating to the top and on its side will expose the fish to your aquarium lighting and warm it up.

    3. There’s A Lack Of Oxygen In The Water Column

    Another possible reason for this type of behavior is that your Betta fish might not get enough oxygen from the water.

    It could be that the water is too shallow, there’s not enough oxygenation going on, or there are too many fishes sharing the oxygen.

    The surface of the aquarium is where oxygenation occurs.

    Oxygenation is the process where oxygen molecules integrate into the water.

    In other words, it’s how your fish can “breathe” in the aquarium.

    In large bodies of water, oxygenation is assured because of the large surface area of a lake, river, or creek.

    It’s also agitated when the water moves, increasing the amount of breathable “air” in the water.

    But things are different in your aquarium.

    A closed system like that has a very limited surface area, and very little oxygenation occurs.

    When there’s not enough oxygen in the water to go around, fish like Bettas tend to go to the surface to get some precious air.

    Not just that, but Bettas are also part of a species called labyrinth fish.

    These types of fish can supplement their breathing by taking air directly from the surface, which might be why you can see your Betta go to the surface every once in a while.

    4. The Aquarium Water May Be Polluted

    Your Betta might also be exhibiting this behavior because the water in your aquarium is polluted.

    Now, the problem is much more obvious if your aquarium is visibly green, gray, or brown.

    After all, your Betta’s home should always be crystal clear water.

    But your aquarium can still be polluted even if it’s crystal clear. Invisible elements such as ammonia, nitrites, and nitrates are invisible to the naked eye, but they’re extremely toxic to your fish and can cause them to try and escape the pollution by going upwards.

    These chemicals are naturally released when organic matter from your fish breaks down.

    If your Betta tank filter doesn’t have the right biological filtration, these will stay in your aquarium.

    When this happens, your Bettas will run out of oxygen to breathe from the water column and try to go up to breathe.

    Make sure that you have a good filtration system in your Betta tank, such as those offered by the Aqueon QuietFlow Internal Power Filter and the AquaClear Power Filter.

    5. It May Have Swim Bladder Problems

    Fish have an organ called the swim bladder.

    This is the organ responsible for their buoyancy, or how much they float.

    They fill the swim bladder with air to float up and then decrease the air when they want to dive deeper.

    This way, your Betta’s swimming is controlled in large part by their swim bladder.

    So when this specialized organ faces some problems, you can imagine how it would wreak havoc with your poor pet’s ability to swim.

    Your Betta may have gotten a swim bladder disorder through injury, disease, or birth defect.

    This is the general term for problems with that organ, and the effect would be that your Betta won’t be able to swim properly. Thus, they’re going to either sink – or float up.

    Swim bladder disease may only be temporary, but in some cases, the disease is permanent.

    In the latter case, your fish is in critical condition.

    You can take it to the vet, especially one that specializes in small animals, but it’s unlikely that they will be able to do much.

    6. It May Be Highly Stressed

    Like humans, fish behavior can also be drastically altered by how much stress they’re in.

    If your Betta fish is experiencing a fair bit of stress, this could lead them to unexpected behaviors such as floating sideways.

    There are plenty of possible causes of stress in fish.

    Some external factors could include frequent water agitation.

    Fish tend to become very stressed when there are constant loud noises outside the aquarium or if their water is frequently disturbed by movement or other people.

    Events such as heavy construction outside your house or children heedlessly playing with your Betta’s aquarium water could achieve this effect.

    However, the source of the stress could come from within the aquarium itself.

    Your tank could be overcrowded, or your Betta might be bullied by another Betta or a school of aggressive fishes such as tiger barbs.

    Stress can accumulate in your fish until they are either overly paranoid or become catatonic.

    7. There’s A Lack Of Stimulation In The Tank

    Like other humans and animals, your Betta also needs stimulation to keep its attention.

    They are naturally curious and interactive, so they need something to occupy them, whether that’s aquarium plants to explore or other (non-threatening) animals to keep them company.

    In the wild, Betta fishes often roam and guard their territory, and there’s plenty of natural stimulation to interest them.

    That’s not the case for most aquariums.

    They can get incredibly bored if they are kept in a small, bare area with nothing to do except float.

    When this happens, your fish can get stressed, and that might accumulate.

    That’s why it’s important to keep them in a tank of at least five gallons.

    If you want them to have a companion, like a snail, it’s best to keep them in at least ten gallons.

    Alternatively, since Bettas are smart fishes, they might notice that floating like that usually elicits a response from you, and they’ll try to do that to have something to do.

    8. The Spawning Season Has Started

    Another possible reason why your Betta might be acting this way is that it might be preparing for spawning.

    Bettas have mating seasons, and in these mating seasons, the males prepare by creating a bubble nest.

    The bubble nests serve several purposes.

    In the wild, Bettas live in slow-moving, murky, shallow water with little oxygen, so putting their eggs high up on the surface of the water body gives their eggs better chances to hatch.

    Plus, the bubble nest will house all the Betta eggs until they are ready to hatch, while the male Betta guards it against predators.

    To create the bubbles, your male Betta takes air from the surface and uses the mucus it naturally produces to bunch them up.

    Doing this will put Betta males in awkward positions as they try to arrange their nests just the way they like it, which might be one of the reasons why you can see your Betta floating on its side.

    9. It May Be In Shock

    Shock is a mental state that many of us are familiar with.

    When a person is in shock, their cognitive abilities are reduced, and their responses are dulled.

    In short, humans often become unresponsive.

    The same can also happen to animals, even Betta fishes.

    Shock can occur because of a variety of different things.

    It could be cumulative stress, sudden grievous injury, or it might be suffering from an illness.

    This is frequently observed if the fish is placed in a high-stress situation suddenly.

    For example, a cat might have found its way to your aquarium and vigorously hunted your fish down.

    Or a child might have reached into the tank and chased the fish around with their hand.

    Events like these could put your Betta fish in shock, and it could make them float up to the top and on their side.

    10. It May Have Died

    Perhaps the most gruesome possibility to contemplate, your Betta fish may have died, and this is the natural position that they assume in their death.

    Whether through old age, disease, or stress, losing a beloved Betta fish is painful, but you need to recognize the signs so that you can begin grieving for your pet.

    Hygiene is also important; you will want to remove the corpse quickly before it can begin to foul up the aquarium water for other inhabitants.

    When a Betta fish is floating upwards and on its sides, observe it properly to see if some part of it is still moving.

    If you can’t tell, touching it gently with your finger can reveal if it’s just bored or in shock.

    You’re in the clear if it still moves once your finger touches it.

    What To Do When Your Betta Is Floating To The Top And On Its Side

    betta fish staying at top of tank

    Now you know the possible reasons why your Betta fish might be acting this way.

    But how does this help?

    You would just be as distressed if you didn’t know the next few steps.

    Thus, this section will discuss the immediate steps you should take if you find your Betta in this position.

    Step 1: Observe

    The very first step is to carefully observe what is happening.

    Don’t panic and do something drastic like take your fish out of the water.

    Try to proceed calmly while observing the fish.

    You need to be extremely cautious about your judgment because you don’t know what’s happening yet.

    Take note of the possible reasons that the fish might be acting that way.

    Is the water too cold? Too hot?

    Is the tank overcrowded, or did you notice any would or rips in its fins that might indicate harassment?

    You can also take some water measurements.

    Measure the basics: pH, ammonia, nitrates, nitrites. A sudden spike might have caused shock.

    To take these measurements, I reccommend the API Freshwater Master Test Kit, which helps in checking for changes in water parameters.

    Step 2: Determine If It’s Still Alive

    The next thing you will need to urgently do is determine if your fish is still alive.

    You can do this by carefully observing the floating fish.

    Look for signs of movement in the gills and tail.

    If you can’t find anything, gently prodding the fish will most likely cause it to move.

    If it’s still moving, proceed with the next few steps.

    However, if your Betta isn’t moving anymore, then proceed to step five.

    Step 3: Transfer Your Betta

    If your Betta is still alive, you should think about transferring it to another tank.

    However, you should properly evaluate the situation first as mentioned in step one, because some situations transferring to a new tank will not fix.

    However, isolating your Betta can do wonders in some situations, such as the following:

    • If there are too many fishes in a tank, transferring your Betta to a place where it can be alone can help them recover from their stress.
    • Similarly, transferring your Betta to another tank is also an effective immediate fix if it is being bullied and harassed by other fishes in your tank.
    • Bad water parameters. If the tank is visibly dirty and your parameter test results show that your tank’s water has high levels of ammonia, nitrate, nitrite, etc., then transferring your beta to a quarantine tank with better levels would be best.
    • Lack of stimulation. In this instance, you’ll likely need to renovate your Betta’s tank, so transferring it to a temporary aquarium will avoid further stressors.

    If the problem seems to be easily fixable, such as water temperature or aeration (by both a heater and an aerator), then you don’t have to transfer your Betta and instead just work on solving those specific issues.

    Step 4: Bring It To The Vet

    Sometimes, the cause of your Betta floating upward and to the side is much more serious than temperature, parameters, or stress.

    It could be sick, injured, or sustained an injury to its swim bladder.

    When this happens, the best thing to do would be to take the fish to the vet.

    You can conclude that the fish needs to go to the vet if you can’t find any internal or external stressors, if the water parameters are healthy, and if your Betta has never acted this way in the past.

    However, keep in mind that while vets might be able to do something, Bettas are extremely small and sensitive animals, and most vets aren’t specialized to deal with their problems.

    Thus, bringing them to the vet will only be a possible solution – it won’t assure that your Betta will heal completely.

    Step 5: Take It Out To Clean Up The Tank

    Lastly, in the event of the most unfortunate death, the best thing to do would be to take your Betta fish out of the tank.

    The sooner, the better.

    One of the main reasons that call for the immediate disposal of your fish is decay.

    If you wait too long, your fish will start to decompose and release harmful elements into the water, which can foul it up for other residents of the tank.

    The second would be the potential for disease.

    Depending on what your fish may have died off, it’s better to clean the tank up immediately to avoid being a possible vector for disease.

    A quick and efficient clean-up is not just beneficial for the other inhabitants of your aquarium, but it’s also better for your mental health.

    The loss of a pet can be overwhelming.

    Give yourself time to grieve, but the sooner you can move on, the better it will be for your health.

    Preventing Bettas From Floating To The Top And On Their Sides

    betta fish floating on its side

    Bettas don’t always end up floating on the surface of the water on their sides, but it’s not that uncommon of sight either.

    Even though you now know what you can do in case you find yourself in this situation, a good aquarist will still prevent it from happening in the first place.

    This section will discuss a few tips to help you avoid these types of issues in the future.

    • Maintain pristine water quality. Bad water quality is one of the most serious reasons why your Betta might end up floating to the top of your tank. Ensure that the temperature, oxygen, pH, nitrite, nitrate, etc. levels are all within your Betta’s tolerated range.
    • Keep your fish engaged. To avoid boredom, ensure that your Betta has plenty of spots to explore and interact with in your aquarium. These could be live plants, invertebrates like shrimp, snails, decor, and more.
    • Buy from reliable breeders. Many Betta breeders hide abuses that can be masked by the time the Betta is displayed. Rampant overcrowding, mistreatment, inbreeding, and a lack of safeguards against diseases can make the Bettas you buy sickly and prone to contracting or spreading diseases.
    • Feed your fish a healthy diet. Similarly, keeping your Betta healthy by feeding a balanced, varied, and high-nutrition diet like Fluval Bug Bites and Tetra Betta Small Pellets should be a habit. Healthy Bettas are less likely to be affected by internal or external conditions.
    • Don’t overcrowd the aquarium. Lastly, make sure not to put too many fish in one spot. Even if you over-filter to up with the bioload, your Betta will be stressed all the time and may need to be transferred.


    Bettas are one of the most interesting creatures to own and care for, so as responsible owners, we need to know what to do in emergencies.

    This article discussed the main reasons why you might find your beloved Betta floating to the top and on their side, plus the steps you can take to take care of it and prevent it from happening again.

    Now, you should be more equipped to handle these types of crises and able to give your Bettas a long and fulfilling life.

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