Popeye Fish: Causes, Symptoms & Treatment

Popeye fish (Exophthalmia) is a condition that causing fish’s eyes to become enlarged and protruding from their heads.

This condition is caused by a variety of reasons, such as bacterial and viral infections and supersaturation of environmental gases.

Symptoms of the condition include cloudy bulging eyes, lethargy, and loss of appetite. Treatment includes a combination of antibiotics and good husbandry practices.

Early diagnosis and treatment of Popeye is essential to preventing serious health problems in fish.

Popeye Fish

What is Popeye in Fish

Popeye is characterized by the swelling of the fish’s eyeballs and can be caused by a number of different factors, including poor water quality, pathogenic infection, stress, and injury.

It causes the eye to swell up and stick out from the body. Basically, It is a bacterial infection that affects fish.

The bacteria enter through the fish’s gills and multiply rapidly, causing inflammation and swelling of the head and body.

What Causes Popeye (Exophthalmia) in Fish

Gas Supersaturation

Furthermore, certain gases pose a threat to fish and other aquatic life if they are introduced in the environment.

Water that flows from springs and wells or is pumped from wells is often saturated with dissolved gases. Often they contain the same substances as atmospheric air.

Without controlled release or saturation of chemicals in cultured environment, aquatic life, or in wild lakes and pools, these risks continue.

Supersaturated gases in a typical habitat, or conventional aquarium, are a threat to organisms.

If dissolved chemical elements are made of substances such as nitrogen, monazite, krypton, argon, and neon, they will biologically insert and tend to release into body cavity of fishes.

Abdominal cavity, intercellular spaces, and the cavity behind the eyes are the most commonly affected parts of the body by the accumulation of gases.

Oxygen released in body cavities is absorbed into the bloodstream by the blood plasma.

If particles accumulate behind the eyeballs, these bubbles can be responsible for Popeye. These air bubbles could be the source of the nickname gas “Popeye.”

Physical Injury

Fish Popeye is caused by trauma or injury. It is caused by trauma to the eyes. Usually, only one eye is affected, so the condition is more likely due to an injury than to a chemical imbalance.

If only one fish in a group shows signs of Popeye, it is probably because of an injury. Scratching an eye may lead to swelling and loss of vision.

Aeromonas & Pseudomonas Infection

Aeromonas and Pseudomonas are common Gram-negative bacteria that can infect fish. One of the most common symptoms of these infections is exophthalmia, or Popeye.

Bacteria produces a toxin that damages the fish’s eyesight. This makes it difficult for the fish to feed or swim correctly, which can lead to death.

Enteric Red Mouth

Popeye is a condition that results when fish are infected with enteric red mouth disease.

This disease is caused by a bacteria called Enterobacter Yersinia ruckeri, which is found in contaminated food or water.

Salmonid fish enteric red mouth disease (ERM) is an acute septicemic bacterial illness of salmonid fish species caused by Yersinia ruckeri, a Gram-negative rod-shaped enterobacterium.

Viral Hemorrhagic Septicemia (VHS) Infection

Viral hemorrhagic septicemia (VHS) is a deadly virus that affects fish. The virus is spread through contact with contaminated water, and can cause severe bleeding and death in fish.

VHS can also cause exophthalmia, or Popeye, in fish. This condition results in the swelling of the eyes, and can eventually lead to blindness.

Internal Injuries

Popeye is usually seen in both eyes. Fish infected with this condition usually suffer from internal problems. Such problems include kidney failure and a metabolic disorder.

Water conditions can also contribute to this problem. If you notice any signs of gas accumulation in your fish’s eyes, then you need to check your water parameters.

Signs & Symptoms of Fish Popeye (Exophthalmia)

Popeye’s disease is an disorder that affects the muscles that control the movement of the eyeballs. This disease affects one or both of the fish’s eyes.

Gas bubble form in the blood and visible on external surfaces of the skin and in the oral cavity and eye sockets of fish.

The most popular symptoms identified were swimming in isolation prior to erratic behavior and refusing to eat.

-Fish Eyes having severe infections may contain high concentrations of fluid. Eye problems, such as corneal opacity or cloudiness, were seen.

Carps pop eye

Diagnosis of Fish Popeye (Exophthalmia)

Popeye’s disease affects the muscles of the eye. This causes the eyeball to become enlarged. When this happens, your vision gets blurry.

The fish may have a noticeable change in its appearance. Loss of appetite and fish act sickly.

The gills may turn pale and eroded, and the scales may stick out. The fish may have clamped fins and be lethargic.

How To Prevent Popeye Disease (Exophthalmia)

It is important to prevent the spread of the virus by practicing good hygiene and keeping fish tanks clean.

Properly Measure the Gas Concentration

If you keep fish as pets, you know that they need clean water to stay alive. But did you know that the quality of the water is just as important as the quantity? One water quality issue that is often overlooked is gas concentration.

Many factors can affect gas concentration in aquariums and ponds, including temperature, filtration, and aeration. If the levels are too high, it can be fatal for your fish.

Properly measure the gas concentration. This can be done with a simple test kit from your local pet store. Once you know the levels, you can take steps to adjust them as needed.

Temperature is one of the biggest factors affecting gas concentration. As water warms, it holds less dissolved oxygen and off-gasses more carbon dioxide.

Proper Monitoring of Water & Partial Water Change

Monitoring the aquarium water chemistry and observing your fish daily can help you avoid this disorder.

Replacement of cloudy water with clean water should be helpful for maintaining proper water quality.

However, if the tank is well maintained, partial water changes are performed regularly, and the fish are fed nutritional food, the odds of Popeye striking are greatly diminished.

Proper Feeding Management

Popeye is caused by improper feeding or too much ammonia in the water. It could also be due to bacteria or other diseases.

To prevent Popeye, you should monitor the pH level of the water and feed the fish properly. You must maintain the proper amount of ammonia in the water.

Popeye (Exophthalmia) Fish Treatment

How to treat Popeye in farm and aquarium fish are given below,

Degas Water

A fish culturist whose water source is saturated with inert gases may use many different types of gas release devices to release the gas from the affected water.

Usually, agitation of the water is necessary. Devices used are for releasing the oxygen in the water (aeration) can be used to degas water.

Test Water Quality

Test the water in the tank before adding new fish. Make sure that the pH level and temperature are within the accepted range for your fish. Daily water changes are essential to maintain safe conditions for the other fish in the aquarium.

Using Epsom Salts

Epsom salt is useful for treating inflammation, swelling, and infections. Salt should be left alone for about ten minutes.

It is suggested to use either Epsom salt or aquarium salt to treat popeye. Epsom salt is gentler on fish than aquarium salt.

How much salt do I add to treat popeye disease?

For the salt treatment, he should be left in the saltwater for about 5-8 minutes. Fish should be moved to a separate tank before being treated with salt.

Antibiotic Treatment

Antibiotics treatment or antifungal medications are effective against fish eye infections. Antibiotic medications are administered orally.

Broad-spectrum antibiotics are given to treat internal infections. The dose required can vary depending on the type of antibiotic used and the severity of the infection.

Quarantine the Infected Fish

Remove the infected fish from the aquarium. Place them in a separate hospital/quarantine tank with optimal water conditions (temperature, pH, hardness). Do not put them back together again.

Stop Overfeeding

Fish should never be fed live foods because it could cause an infection. For ensuring a healthy immune system, high-quality feeds should be given to the fish.

Use live foods such as brine shrimp, daphnia, bloodworms, and mosquito larvae.

Tips for Fish Popeye Disease in Aquarium

-Make sure you give the fish enough space to swim around.

-Keep the water clean and avoid adding too many plants or decorations.

-Make sure your water is healthy, and not too acidic or alkaline. Don’t use over-the-counter products without consulting an expert.

-Avoid rough handling of fish. Keep fish away from sharp objects.

Frequently Asked Questions

How serious is Popeye disease?

Popeye disease is a serious and often fatal illness. In recent years, Popeye disease has become more prevalent in fish.

Does Popeye in fish go away?

The good news is that in most cases Popeye can be treated successfully the Popeye in fish go away within a week. Treatment may include antibiotics if the cause is bacterial, antiviral medications if the cause is viral, improving water quality, and/or removal of any toxins from the environment.

Is Popeye in Fish Painful?

Fish may be able to sense when they are injured and stressed that’s why the reduce feed intake and normal body movement.

Can Popeye Kill Fish?

Popeye is a symptom of fish internal disease, it can create blindness and kill fish.

Can a fish recover from Popeye?

There is no one definitive answer to this question as to the severity of Popeye, and a fish’s ability to recover from it depends on a variety of factors. In general, however, most fish can overcome the disease if they are given proper care and treatment.

In some cases, it may also be necessary to supplement the fish’s diet with vitamins or medications. With patience and diligent care, most fish will eventually make a full recovery from Popeye.

Is there any need for fish Popeye surgery?

No need, proper treatment may reduce the swelling eye condition


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