Why Is My Neon Tetra Swimming Upside Down?

Neon Tetra Swimming Upside Down

Okay, you may be a fan of a circus but you won’t prefer your neon tetra swimming upside down all the time. It is scary and worrisome when a neon tetra starts to swim strangely all of the sudden. But there is always a hidden reason behind everything happening in the tank. So, what’s up with your neon tetra? Why is neon tetra swimming upside down?

Neon tetra will not behave rationally or strangely unless there is something wrong with them or in the tank. Bloating and Swim Bladder disease are two main reasons for neon tetra swimming upside down in the tank.

These two reasons are treatable but can get fatal quite soon than you expect. So, you might need to learn a little more about this, don’t you think?

In this article, you will find answers to every question that lingers behind your head when you see your neon tetra swimming upside down.

Why Is My Neon Tetra Swimming Upside Down?

To be honest, if your neon tetra has started swimming upside down, then there is a high possibility that your neon tetra is been suffering for quite a long time.

The buoyancy issue intervenes when your neon tetra starts to behave the way you are describing. They will be very much alive and active yet swim strangely making you worry more

There are two main reasons for neon tetra to swim strangely in the tank. Let me list them below for you:

Swim Bladder Disease

The malfunction of the swim bladder of neon tetra is the main culprit hampering the buoyancy and causing the swimming issue.

You might like to learn more about Tetra Fish Diseases and Treatments

Swim bladder disease makes neon tetra swim upside down and trusts me they have no control over it. They are not doing that intentionally.

Neon tetra will not be able to maintain the balance and keep getting rotated upside down every time they try to get normal.


Sometimes, bloating causes neon tetra to lose their balance and turn upside down while swimming. The swollen-up belly is definitely a nightmare neon tetra will be living with.

Dropsy comes with a cluster of signs and bloating is one of them. But hope for a different reason here.

What Are The Causes Of Neon Tetra Swimming Upside Down?

Each of the reasons has a very definite cause for occurring in neon tetra. You need to know the root cause before preventing or curing it.

Without knowing what is happening with the fish, how will you protect them? Let me help you.

Cause Of Swim Bladder Disease

The main cause of swim bladder disease is uneven eating that makes their body exposed to sir. After overfeeding, neon tetra gulp in more air just so they can regulate buoyancy.

Poor Neon Tetra! Constipation, bacteria, etc. will invite buoyancy disorder to your neon tetra and hence affects the swim bladder.

Constipation will cause the bloated stomach to press down the swim bladder and hence the swim bladder disease.

Sometimes the birth deformation of the swim bladder is the main reason why your neon tetra will be swimming strangely.

Nitrate intoxication is one of the super-villains of swim bladder disease that hides in plain sight.

Cause Of Bloating

Swollen belly and bloating are the symptoms of Dropsy. And Dropsy is caused by various bacteria that are present in the aquarium and will infect neon tetra when the water parameters fail to meet the optimum criteria.

However, this might not be the case here and excess swallowed air might be the prime reason for bloating in neon tetra.

Just hope for positivity here because trust me, you won’t prefer dropsy in your fish. Nightmare Alert!!!!

How To Treat The Different Conditions That Cause Neon Tetra Swimming Upside Down?

Now, let us know how can you treat these diseases and save neon tetra as soon as possible. You might not like looking at neon tetra swimming upside down all the time.

To be honest, your neon tetra will be dead due to these reasons if you don’t take action immediately.

Treatment Of Swim Bladder Disease

Here is what you need to do if your fish is suffering from swim bladder disease. Each cause has a different solution.

Let’s discuss it separately.

Swim Bladder Disease Due To Constipation Treatment

Feed your neon tetra fibrous food and you will be able to treat them more effectively. But some experts approach the fasting process but I recommend you to feed them.

Thaw a pea, boil it, peel its skin off, soak it in the water once again, and finally feed your neon tetra that very cooked pea. Let the pea do its job and skip feeding anything to your neon tetra for the next 24 hours.

And please remember to remove the residual food and cleaning the tank. Or else you will invite other issues to your fish tank.

Daphnia can also be a good choice here. And if your neon tetra is showing no appetite then you have no options other than to let it fast for 3 days.

Swim Bladder Disease Caused Due To Bacterial Infection

Take your fish to the vet. Truly, this is way complicated than you think. You need to test the liquid inside the bloated part of the fish that is causing the trouble and use the antibiotic accordingly.

Swim Bladder Disease Due To Birth Deformation Of Swim Bladder

When it is a birth defect, then sorry my friend there is very little you can do. You will have to just make sure your neon tetra is happy in the tank till it lives.

Special care can assure the longevity of the neon tetra but if the condition is untreatable and already have cysts in it, then sorry my friend, pray for a simple and painless death for your fish.

Swim Bladder Disease Due To Improper Water Quality Treatment

Just check the level of ammonia and nitrite level in the tank and maintain it zero all the time. Change 40% water each day once neon tetra starts swimming upside down.

Even the level of nitrate needs to be less than 15 ppm. Remove 5 to 10% water every hour to lessen or completely avoid giving another chemical shock to your neon tetra.

Relocating your fish to the tank with proper water parameters will also be an ideal solution here.

Treatment Of Bloating

You see your frenzy-eating neon tetra will gulp more air after overfeeding so here is what you can do for overcoming this bloating and upside-down swimming circus of neon tetra.

Just feed them the boiled pea and this treatment as done for the constipation problem will be enough.

How To Prevent The Different Conditions That Cause Neon Tetra Swimming Upside Down?

Prevention is better than cure and this phrase should always be your motto while raising neon tetra in the tank. One miss, game finish. So, don’t take a risk here.

Here is what you need to do to stop neon tetra from getting swim bladder disease or anything that will cause them to swim upside down.

  1. Feed them food in an appropriate size. Not more, not less. Just in exact proportion every day. Quit Overfeeding your neon tetra
  2. Maintain the water parameters optimum all the time.
  3. Feed them a variety of food including fibrous food more.
  4. Use proper filtration methods to clean the water and maintain its quality.

Frequently Asked Questions

Here are answers to few FAQs you might be wondering about.

Is Swim Bladder Disease Fatal For Neon Tetra?

No, most of the time it can be cured, however, sometimes this will disappoint you. Prevention is better than cure, my friend.

Don’t let your neon tetra die from something that can be easily cured. Swim bladder disease can get fatal once you neglect it or else it can be easily treated with a simple change in best dietary plans and water parameters for neon tetras.


In Conclusion, neon tetra swimming upside down is a true nightmare, I know it. I have been through that nightmare and came out unharmed and safe. I hope you do the same and follow my instructions properly. Your neon tetra depends on you for every little need so please act like a responsible fish parent. You will have a healthy and happily swimming neon tetra if you follow my instructions properly.

And if you still have a query, I am here to help. Just Drop a comment below.

Good Luck!!

Happy Fishkeeping!!!

Recommended Articles:

  1. Neon Tetra Behavior: Are They Aggressive/Fighting or Playing? Find out here.
  2. How Long Can Neon Tetras Live Without Food

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