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My goldfish has Popeye. What medicine should I use to treat it?

Updated on September 23rd, 2025

Pet's info: Fish | Unknown - Fish | Male | unneutered

I have a black moor gold fish who has a severe case of Popeye I quarantined him in a separate , but I’m not sure what medication to use for him .

2 Answers

Most Helpful Answer

Answered By Angel Alvarado, LVT

Licensed Veterinary Technician

Published on October 27th, 2017

Popeye is a symptom of an underlying disorder in the tank. It can be a result of trauma or infection. Most cases can be managed by maintaining water quality and a broad spectrum antibiotic. Quarantining as you have done is always a good move. Check the tank for any furniture/décor that may cause injury. Check the water chemistry, filtration and temperature next. Any imbalances can predispose a fish to illness. Partial water changes can be done to improve quality and correct imbalances. Use only aged or conditioned water that is temperature matched to prevent further stress or shock.
Maracyn Plus or Kanaplex can be found in the aquarium section of the local Petco or fish store. You can use either, in addition to plain aquarium salt (NOT table salt), to treat. Dissolve 1 teaspoon of salt per gallon of water in a cup of tank water and gently pour it into the tank. Treat for 10-14 days with salt then perform partial water changes to decrease salinity. Treat only the amount of water going back into the tank with salt to avoid overdosing.

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Angel Alvarado, LVT
Licensed Veterinary Technician
Published on October 27th, 2017
Popeye and a cloudy eye may indicate injury, infection or poor water quality. Check the tank for plants and furniture that may cause trauma. Tank mates can also cause injury. Test the water with a home test
kit or submit a sample for testing. Most pet or fish stores will do this for free or for a nominal fee. Ammonia and nitrites should be 0.25ppm or less, nitrates can be 40ppm or less. Daily 30% water changes may resolve the condition by improving water quality. Use only aged or conditioned water that is temperature matched to prevent stress or shock. If Boris has tank mates, consider separating him out to a hospital tank until he recovers.
If water changes do not resolve the condition, consider a broad spectrum antibiotic. You can find one in the aquarium section of the local pet or fish store. Read package directions carefully and remove the carbon filter insert if indicated. Plain aquarium salt (NOT table salt) can also be used as a general tonic, to reduce stress and aid in recovery. Dissolve 1 teaspoon of salt into a cup of tank water and gently pour it into the tank. If performing daily water changes, use only enough salt in the water that is being replaced, not the entire volume of the tank.
1Pet Parents found this answer helpful

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