What Does It Mean When a Betta Fish Has a Swollen Eye

Betta fish are one of the most popular aquarium fish. They are small, colorful, and easy to care for. Bettas are often considered pets because they are so easy to take care of and they don’t require a lot of space. Bettas do best in a tank with plenty of plants and other small fish to keep them company.

When a betta fish has swollen eyes, it means that they are in distress. This can be caused by a variety of factors, such as being overcrowded, not having enough oxygen, or being stressed out. If you notice that your betta is swimming around in a panicked manner or has swollen eyes, it is best to take them to a veterinarian as soon as possible.

Two red betta fish is fighting with beautiful gestures in black background.

What Is Popeye in Betta Fish?

Popeye disease is a common bacterial infection in betta fish. Popeye disease is a common ailment in betta fish. It is caused by a parasite and can be fatal if not treated quickly. The parasite enters the fish through its mouth and migrates to the fish’s eyes. There, it causes the fish to swell up and die. The best way to avoid popeye disease is to keep your betta fish clean and healthy. Symptoms of the disease include swollen eyes, lethargy, and poor appetite. Treatment involves antibiotics and water changes. If left untreated, the disease can lead to death.

Unilateral Popeye Disease

Unilateral popeye disease is a condition that affects the eyes of betta fish which is an effect of physical damage to the fish. This disease can lead to blindness in the fish. Treatment for unilateral popeye disease is typical with antibiotics. If you notice any of these signs in your pet betta fish, it is important to take them to a veterinarian for evaluation.

Bilateral Popeye Disease

Bilateral popeye disease is a common ailment in betta fish which is an impact of poor water conditions. It results in the fish’s eyes become enlarged and inflamed. The disease is easily treated with antibiotics but can be fatal if not treated quickly. Bacterial infection is one of the most common causes of bilateral popeye disease in betta fish. This type of infection can cause swollen eyes, poor appetite, and swimming behavior. If you notice any of these symptoms in your pet betta fish, it is important to take them to a veterinarian for evaluation.

beautiful ornamental betta fish, with blur background

What Causes Popeye Disease?

Popeye disease is a condition that affects betta fish. The disease is caused by a virus and can cause the fish to have swollen eyes. The virus can also cause the fish to have a decreased appetite and difficulty swimming. There are a few things that can cause popeye disease in betta fish. The most common causes of the virus are bacteria or parasites. If your pet has popeye disease, there is a good chance that they have been infected by one of these organisms. Bacteria may be the cause of your pet developing swollen eyes and poor appetite while swimming around erratically in their aquarium or pond.

Popeye Caused by Injuries

Betta fish can also develop popeye disease if they are injured. If there is a break in the skin or bone on your pet’s head, they may be more susceptible to getting popeye disease. Concussions and other injuries caused by accidents can also lead to popeye disease. You must take your pet to the vet if they show any signs of injury or illness so that their condition can be evaluated and treated as necessary

Popeye Infections

Popeye is a serious infection of the swim bladder in fish. The swim bladder is a sac that sits behind the stomach and helps to regulate gas and fluid in the body. When popeye infections occur, there can be swelling, color changes, and slurred speech (dysphagia) due to obstruction of airflow into your fish’s body. Treatment for popeye includes antibiotics, fluids therapy, and surgery.

Fighting fish Betta splender Fighting fish and Reflection mirror reflection in black background.

What Are the Signs and Symptoms of Popeye Disease?

There are a few symptoms that may indicate that your pet has popeye disease. The most common symptom is the fish having swollen eyes. Other signs of the condition include a decrease in appetite, difficulty swimming, and erratic behavior. If you notice any of these signs in your betta fish, it is important to take them to a veterinarian for evaluation.

Popeye disease is a common and deadly disease affecting both freshwater and saltwater fish. The disease is caused by a bacterium and can be fatal in fish if not treated quickly. Some of the signs of popeye disease in aquarium fish include swollen eyes, redness, and discharge from the eyes. If you notice any of these signs in your fish, it is important to take them to a veterinarian as soon as possible for diagnosis and treatment.

How to Prevent and Treat Popeye Disease?

There are a few ways to prevent popeye in betta fish, but the most effective way is to keep them in a separate tank with only other betta fish. If your betta fish does develop popeye, you can treat it with antibiotics or by giving them food that has been soaked in water that has been mixed with a teaspoon of salt. Other tips include:

Water Treatment

If you’re concerned that your betta might be infected with popeye, there are a few things you can do to help make sure the fish is healthy. One of the first things you should do is treat the water in which your betta fish live- both tap water and filtered water- with a bacteria filter. This will help reduce levels of bacteria that could cause an infection in your fish. And finally, if possible, try to keep your betta fish in a separate tank so they can’t spread popeye to other fish.


If you can’t prevent your betta fish from getting popeye, there is a solution: medications. Some of the most common antibiotics used to treat infections in fish include nalidixic acid and enrofloxacin (both prescribed by your veterinarian). Your vet will prescribe the right antibiotic for your particular situation, and it’s important to follow their instructions carefully.


If medication is not an option, one last resort is using a topical treatment called Melafix. This medication can be applied to your fish’s eyes and will help heal them. However, it should only be used in cases where other forms of treatment have failed or if your fish is already very sick with popeye.



Epsom Salt

If you suspect your fish has popeye disease, you can treat it by giving the fish Epsom salt. Epsom salt has been shown to help remove toxins and minerals from the body and can help cure the fish of its viral infection. Always consult a veterinarian if your fish is exhibiting any signs of health problems, such as swollen eyes or difficulty breathing.


In some cases, surgery may be required to remove the enlarged eyes and popeye. This is a serious condition and should only be treated by a veterinarian if all other measures have failed.

What Is the Prognosis of Popeye Disease?

The prognosis of popeye disease is typically very poor. The eyes can become so large and misshapen that the fish cannot see and may eventually die from malnutrition or lack of oxygen. Prevention is the best way to avoid this problem, but if it does occur, treatments are available to help improve the fish’s health.

The prognosis for fish with popeye disease is typically good but can vary depending on the severity of the infection. Treatment with antibiotics, if necessary, can usually cure the fish. However, in some cases, the fish may develop a swollen eye, which can be a sign of a more serious infection. If this occurs, the fish should be treated immediately and monitored closely by a veterinarian.

Is Popeye Disease Contagious?

No, popeye disease is not contagious. However, if a fish has popeye disease, it may be easier for other fish to catch the virus and get sick. If you have any questions about whether your fish has caught popeye disease or not, please contact your veterinarian.