Why is My Fish Swimming Sideways? Causes and Treatment

Fish swimming sideways is a common sight in aquariums and can be a cause for concern. 

It’s important to understand that there can be several reasons why a fish may swim sideways, including swim bladder problems, neurological issues, or even environmental factors such as poor water quality. 

Swim bladder problems are one of the most common reasons why fish swim sideways, as the swim bladder helps fish maintain their buoyancy and balance in the water. 

When the swim bladder is damaged or infected, it can cause the fish to swim sideways or even float to the surface. In some cases, swimming sideways may also be a sign of a more serious underlying health issue. 

In this article, we’ll explore the different reasons why fish swim sideways and what you can do to help your fish regain its normal swimming behavior.

Why Is My Fish Swimming Sideways?

Your fish might be swimming sideways due to various reasons like swim bladder disorder, injury, stress, and water quality issues. 

Let’s dive into some primary causes and what you can do to help your fish:

  • Swim bladder disease: A swim bladder is an internal organ that helps maintain your fish’s buoyancy. Any disorder can make fish lose balance and swim sideways.
  • Overfeeding: Feeding too much might lead to digestion problems, affecting the fish’s swim bladder and swimming pattern.
  • Water quality: Check your tank’s ammonia, nitrite, and nitrate levels, as well as the temperature, to ensure a healthy environment for your fish.

Maintain a suitable aquarium environment, feed your fish properly, and monitor their behavior. 

Don’t hesitate to consult a veterinarian if needed. 

What Is Swim Bladder Disease?

Swim bladder disease is a common issue that might cause your fish to swim sideways. 

It occurs when a fish’s swim bladder, a gas-filled organ responsible for maintaining buoyancy, isn’t functioning correctly. This could be due to various factors like injury, stress, or water quality issues.

You don’t need to be a fish expert to understand the importance of a healthy swim bladder. 

Imagine trying to float in a pool with deflated floaties—that’s how your fish feels! 

Ensuring your fish has a well-maintained aquarium environment, proper feeding habits, and regular monitoring will help avoid swim bladder problems. 

Be sure to consult a veterinarian if needed so that your fish can swim happily and healthily.

What Causes Swim Bladder Disease?

What Causes Swim Bladder Disease

Swim bladder disease can occur for various reasons, and it’s essential to understand the common causes to prevent and treat this condition in your fish.

Take a look at the most common factors that cause swim bladder disease in fish:

Improper Feeding

Feeding your fish the wrong type or amount of food can lead to swim bladder issues. 

Overfeeding or feeding foods that expand in the fish’s stomach can cause pressure on the swim bladder, affecting its function. 

To avoid this, make sure to feed your fish a balanced diet, and avoid overfeeding.

Low Water Temperature

Fish are sensitive to changes in water temperature, and a sudden drop can negatively impact their swim bladder. 

Colder water slows down their metabolism, making it harder for them to properly digest food. This can also lead to swim bladder problems. 

Maintain a stable temperature in your aquarium within the species’ recommended range.

Enlarged Abdominal Organs

Sometimes, enlarged organs in the fish’s abdomen, such as the liver or intestines, can put pressure on the swim bladder. This can make it difficult for the fish to control its buoyancy. 

In these cases, it’s essential to identify the cause of the organ enlargement and consult with a veterinarian for proper treatment.


Parasites can infect a fish’s swim bladder, leading to its inability to function correctly. 

In these cases, the fish may require medical treatment to eliminate the parasites and restore its swim bladder function.

Keep a close eye on your fish’s behavior and, if you suspect a parasitic infection, consult a vet immediately.

Bacterial Infection

Bacterial infections can also damage a fish’s swim bladder, causing it to lose its ability to control buoyancy. 

Regularly testing water quality and maintaining proper aquarium hygiene is crucial to avoid bacterial infections. 

If you notice signs of illness in your fish, consult a vet to diagnose and treat the underlying cause.

Treatments and Prevention

Swim bladder disease is a common condition that affects many species of fish and can cause them to swim sideways, float to the surface, or sink to the bottom of the tank. 

Fortunately, there are several ways to treat and prevent swim bladder disease in fish.

Home Remedies and Medications

If your fish is swimming sideways, it might be due to swim bladder disease.

One effective home remedy is feeding your fish a frozen pea that has been shelled, microwaved, and cooled down. 

This can help with digestion and relieve pressure on the swim bladder. 

For betta fish, daphnia can also be a beneficial alternative to a pea.

In cases of infection, you may need to consult a vet or use over-the-counter antibiotics to treat your fish.

Proper Feeding and Diet

Overfeeding is a common cause of swim bladder issues, so make sure to avoid it. 

Feed your fish small amounts, only as much as they can eat in a few minutes, and make sure to remove any uneaten food.

It’s best to provide your fish with high-quality pellets or flakes and offer a variety of foods, including live or frozen options, to maintain good health and prevent buoyancy issues.

Maintaining Ideal Water Conditions

An essential aspect of preventing swim bladder disease is maintaining ideal water conditions in your tank. 

You should invest in a good-quality test kit, like this one, to ensure proper pH and ammonia levels. 

The ideal temperature, pH, and ammonia levels vary depending on the species of fish, so make sure to research the specific needs of your fish. 

Maintaining clean water helps minimize the risk of infections that could cause swim bladder problems.

Regular Water Changes and Tank Maintenance

Performing regular water changes is crucial in maintaining optimal water quality.

You should change 25% to 50% of your tank’s water weekly or bi-weekly, depending on the situation and fish species.

Keep the tank clean by removing any debris, algae, and uneaten food. 

Proper filtration is also essential, so be sure to clean or replace your filter media as needed. 

Taking these steps will support good water quality and prevent issues like swim bladder disease in your fish.

FAQs About Why Is My Fish Swimming Sideways

Why Is My Fish Sideways But Still Alive?

If you notice your fish is swimming sideways but is still alive, it could be due to several reasons, including swim bladder disorder, injury, stress, and water quality issues. 

It’s important to identify the cause and take action to help your fish recover.

How Can You Cure Swim Bladder Disease?

Improving water quality, adjusting feeding habits, treating infections, using medications, and adjusting water temperature are effective methods of treating swim bladder disease. 

Proper filtration, regular water changes, and testing the water can help prevent the buildup of harmful toxins. 

Feeding smaller, more frequent meals can prevent overfeeding. Antibiotics and anti-inflammatory drugs can help treat infections. 

Adjusting the water temperature to a comfortable level can prevent swim bladder problems.

Consult a veterinarian or aquatic specialist to determine the appropriate treatment for your fish. 

Is My Fish Suffering with Swim Bladder?

It can be difficult to determine if your fish is suffering from swim bladder disease, as the symptoms can be similar to other health issues. 

Some common signs of swim bladder disease include swimming sideways, floating to the surface, or sinking to the bottom of the tank.

Your fish may also appear bloated or have difficulty swimming. 

If you notice any of these symptoms, it’s important to take action to diagnose and treat the issue.

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