Popeye in fish also called exophthalmus, proptosis, exorbitism, exophthalmia, or exophthalmos is not a specific discus disease itself but describes a condition and can be a symptom of an illness or infection in fish. Pope-eye disease/condition is bulging and swelling of one or both eyes of the aquarium fish. Although it is not difficult to treat the discus popeye, early diagnosis is crucial for successful treatment of the disease. Popeye in discus is sometimes taken mistakenly as cloudy eye condition which is similar to pop-eye especially in its early stages.

Is Popeye a Contagious Disease in Fish?

Discus pop eye is generally not contagious and can be treated with wide spectrum antibiotics which are effective against eye infections.

Can Fish Die from Popeye?

The short answer is Yes! The Popeye condition can be fatal if it is left untreated.

Discus Popeye disease from different angles
Discus Popeye disease from different angles

Diagnosis and Identification of Popeye in Discus Fish

One or both eyes of the discus fish bulge outwards. Like cloudy eye, first symptoms is the outer surface of the fish’s eye which may be white or cloudy. If only one eye is protruding then it is known as unilateral Popeye that is easier to treat, but when both discus eyes are protruding this is called bilateral Popeye that usually implies serious bacterial infection which indicates that the condition is harder to cure. Swelling of the discus’s eye occurs when the fluid produced inside the eye doesn’t drain properly, causing a buildup of painful pressure within the eye, forcing the discus’s eyeball outward. If this fluid buildup and pressure is left untreated, it will cause severe bacterial infection in the eyes, and the eventual result will be blindness and death.

Protruding Eyeball in Discus Fish Eye
Protruding Eyeball in Discus Fish Eye

Pop-Eye Disease Treatments and Cures

As mentioned earlier, If this problem is not detected soon after it is caught, the discus can lose the eyesight in one or both of its eyes. So once you realize that your discus is having the Popeye condition, follow the instructions below ASAP:

  • First of all, you need to do a heavy water change. Sometimes, the pope-eye condition is nothing but a sign of poor water quality especially in cases which only one eye is swollen, or there are more than one fish affected.
  • Adding salt into the water provides numerous benefits including reducing stress and prevention of some secondary infections during the treatment period.
  • Using broad spectrum antibiotics especially those that are effective on eye infections is the best cure for this condition. Neomycin, Kanamycin, and Erythromycin are just some of the best examples.
Swelling and Bulging of Flowerhorn Cichlid Eyes
Swelling and Bulging of Flowerhorn Cichlid Eyes

Fish Medicines

There are also some effective commercial aquarium products for curing fish Popeye disease that can be purchased at almost all local aquarium and pet stores in the USA. Here is a list of some of the most popular fish medicines effective against pop-eye condition in aquarium fish.

Popeye disease in tropical fish
All freshwater & marine tropical fish can get affected by Pop-eye disease

 API® E.M. Erythromycin

A very effective broad spectrum antibiotic from API that cure most of the Pop-eye problems that are caused by bacterial infections.


Another product from API that fight off bacterial infections cause Pop-eye in tropical fish.


Use API FURAN-2™ to cure the most sever forms of the disease. Don’t use this if medication to cure popeye disease in discus if there is not sign of open wounds and sores on or around affected eye.

Seachem KanaPlex™

With the active ingredient of Kanamycin, the KanaPlex™ is a reliable antibiotic to treat most bacterial eye infections including Popeye in fish.