Fish Floating On The Side But Not Dead? Causes And Cures

There are a lot of diseases and infections which our fishes are prone to and we don’t know most of them, have you ever seen your fish floating on the side but not dead or floating upside down then it’s an alarming sign that your fish needs help. It is one of the most common diseases known as the swim bladder disorder which is seen mostly in goldfish and betta fish. 

Fish Floating On The Side But Not Dead

There are a lot of reasons why your fish has a swim bladder disorder and don’t worry just like any other disease this can be cured but with a lot of care and proper attention. If you are here searching for how to cure swim bladder disease then you are at the right place. 

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Why Is My Fish Floating On The Side But Not Dead?

If you have been noticing a different swimming pattern in your fish like floating at the side or floating upside down then it’s a sign of swim bladder disorder that your fish has caught. 

The swim bladder disorder is one of the most common diseases which most goldfish owners go through at least once and assume that their fish is dead. A swim bladder is an organ in fish that regulates the air in and out helping the fish to maintain buoyancy in the water. It helps the fish to rise and dive in the water, when the fish wants to rise at the top of the tank the swim bladder gets filled with gas which makes the fish go upwards and when they need to dive in the gas starts flowing out and that’s the reason you can see tiny air bubbles coming out when fishes swim in depth of the tank.

Swim bladder in Fish

When a fish suffers from swim bladder disorder they have difficulty in maintaining buoyancy in the water and either they stay at the top or float upside down. If this is the issue with your fish then it’s not too late to cure so you should start the treatment immediately. 

Signs Of Swim Bladder Disease?

These are some early warning signs which you will notice in your fish swimming pattern if they have swim bladder disease:

  • Floating at the side of the tank or surface.
  • Floating upside down.
  • Sitting at the bottom of the tank.
  • Standing on its head at the bottom of the tank.

Fish Floating On The Side But Not Dead due to swim bladder

Some other signs involve:

  • No appetite.
  • Distended belly.
  • Curved back.

What Are The Causes Of Swim Bladder Disease In Fish?

These are the causes of swim bladder disease in your fish:


Prevent overfeeding fish

It is one of the most common causes of why your fish has a swim bladder disease. Often we as owners of our pets tend to overfeed them to show our love and care but this can prove dangerous in the case of fish. Overeating can cause constipation in fish, also some of the food items like fish flakes or frozen food if not fed properly they get swollen inside your fish stomach when they get wet.

Water Temperature

Fishes are cold-blooded, which means that their metabolism depends on their body temperature. In cold water, their metabolism slows down which can cause indigestion and result in swim bladder disorder.

Bacterial Infection

Bacterial infection can be a seasonal problem and is responsible for your fish’s bad health.


It might be possible that your fish has caused an injury by striking the tank walls or had a fight with other fish in the tank. 

Birth Defects

Some of the fishes are born with birth defects which can affect the swim bladder in your fish, if your fish has some birth defects you will notice them at an early stage.

How To Cure Swim Bladder Disease In Fish?

There are some ways through which you can cure the swim bladder disease in your fish but before we begin with them you should be ready for any bad news and I would recommend you to take help from an experienced aquarist if you are new to fish keeping. 

Also, it would be better if you take out the diseased fish and put it in another tank till he recovers because this will keep your fish safe from other fishes and the medication will reach diseased fish only. 

NOTE: The swim bladder disease is not contagious so don’t worry it will not spread to other fishes in your tank.

So, let us begin with the cures:

Treating Constipation

There are two ways by which you can treat constipation in your fish. The first is to fast your fish for 3 days until you notice a reduction in the size of your fish’s bloated stomach. Second, feed your fish skinned and cooked peas because peas are rich in fibre and it will improve the digestion of your fish. 

Before feeding your fish with pea, boil and thaw the pea for a few seconds which will make the pea soft then peel the skin of the pea and then you have to soak the pea in water to avoid the pea from swelling inside your fish’s stomach. Now you can feed your fish with pea and hand-feed them if needed but keep one thing in mind that you only have to feed one pea a day, this will let the fibres do their job. 

Another great food option that is rich in fibre content is daphnia, you can buy it from any fish food shop or get it online. 

If your fish is not eating at all then the only option left for you is to starve them for 3 days and let them do this on their own and on the 4th day you can start feeding them one pea a day till you see improvement.

Treating Bloating Or Swallowing Too Much Air

It is also related to the problem of overfeeding which results in constipation. Fishes have two sacks that act as swim bladders and one of them is larger and connected to the stomach so, when you overfeed your fish with uncooked food like fish flakes that do not sink in the water your fish gulp too much air while eating which results in a bloated stomach. The only treatment that will work in this case is feeding your fish boiled pea.

Fixing The Nitrate Levels In Your Fish Tank

Water quality is one of the major reasons for most of the diseases which a fish can get. Overcrowding in your fish tank might be the reason for an increase in nitrate levels in the water, fish produce a lot of waste and especially goldfish. The waste produced by fish is the main cause of increasing nitrate because the waste produces ammonia which converts into nitrites and then finally into nitrates. 

Fix nitrate levels in fish tank

You should check your tank nitrate levels using a liquid water test kit or a test strip on a regular basis for maintaining a good environment for your fish. The ideal amount of nitrate in the tank should be below 15 ppm (parts per million), if it’s more than that your fish have the chance of having swim bladder disease. 

To fix the nitrate levels in your tank you will need to change your tank water by 5-10% every hour and by the end of the day it should be changed by almost 40%. The tank water is changed every hour because this will prevent a sudden change in your tank environment and your fish will adjust slowly. 

Even after changing your tank water by 40% if you still see your fish floating on the side or upside down then you need to clean your filter once. One thing you should keep in mind is that a normal nitrate level below 15 ppm is not harmful to fishes and you should not drop it below this level. Do this process and feed your fish boiled peas and we hope that your fish will be cured in a few days. 

Curing Fish Suffering From Physical Injury

A fish suffering from physical injury can get a swim bladder disease, most of the time a fish gets injured because of being involved in a fight with other aggressive fish breeds or getting injured while in transport. 

The only thing you can do in this case is to keep the diseased fish in a different tank to avoid further fights and take it to a vet. 

Take To A Vet

If you are someone new to fishkeeping or you feel like things have gotten out of your hands then it’s best that you take your fish to a vet. Also, in case of bacterial infection, it would be best to consult a vet before giving any antibiotics to your fish. 

How To Prevent Swim Bladder Disease In Fish?

Well, prevention is always better than cure so it would be better if you take care of these things beforehand so that your fish will never have to suffer from swim bladder disease.

Avoid Overfeeding Your Fish

We all love our pets and sometimes overfeed them. Overfeeding can cause a lot of problems to fishes and one of them is swim bladder. So you need to control your emotions and feed your fish a proper diet from time to time depending upon the species of fish you have.

Avoid Harmful Food

Some fish foods like flakes or pellets are harmful to fishes because they get swollen up once they get inside your fish’s stomach and cause a bloated belly. Avoid these kinds of food items and prefer getting packed bloodworms, shrimps.

Soak Food In Water

Dried foods or frozen food gets expanded once they get into the water and this is one of the causes of the bloated stomach in fishes, so pre-soak your food in water before giving it to your fish.

Regular Water Checks

Keeping a check on the amount of nitrates and oxygen in water is very important for your fish health, we would recommend you to get a water test kit if you are into fishkeeping. 

Maintain Water Temperature

Fish are cold-blooded which means that cold water slows down their metabolism which will slow down their digestion. The ideal water temperature for most of the fishes is 22 to 26.6 °C, at this temperature their digestion will be balanced.

How Long Can A Fish Live With Swim Bladder Disease?

It depends on the condition of your fish which decides how long it will survive. Most of the fishes can survive for a few days if not treated but fishes with birth defects can survive for a long time if taken proper care of.

Also: Betta Fish Not Eating | Possible Reasons and Solutions

Closure | Fish Floating On The Side But Not Dead

Floating fish on the side but not dead or floating upside down is the symptom of one of the most common diseases known as Swim bladder disease. If you witness your fish with this problem you should hurry up and take up action to cure this disease. In this blog post, we have discussed the causes and cures of swim bladder disease that you can read out and help your suffering fish. Also, if things are out of your hands and you aren’t seeing any improvement in your fish’s health then immediately take your fish to a vet.

If you have any questions related to swim bladder disease or have a cure that worked for you, share them with us in the comment section down below.


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