My betta fish has Popeye. How do I treat it and what caused it?

Thanks for reaching out about Minn and including photos, although the lesion can not be identified through the pictures. Is the eye protruding more than the other? Popeye can be caused by multiple problems including an infection, mass behind the eye, increased intra-ocular pressure and more. Many of these are difficult to treat but none of the over-the-counter remedies work. Test and correct water quality for pH, ammonia, nitrites and nitrates. Review diet as pellets/flakes should be purchased every 3 months as vitamins (especially vitamin C) degrade quickly. If continues to progress, a veterinary visit with an experiences aquatic veterinarian is recommended. Good luck.

Thanks for reaching out about Betta. Rarely do the water additives do anything, as fresh water fish do not drink as water passively crosses through gills, into the body due to saline nature of the body. The antibiotic molecules are too large to pass. So water additives might be good for skin lesions (acting as a topical). Not much is known regarding orally administered meds also and how they are intestinally absorbed. Giving antibiotics through injections is the preferred method for success, but a veterinary visit is needed to prescribe. The cause of the pop-eye is the challenge, which could be corneal scratches with secondary infections, bacterial abscess behind the eye, gas bubble disease and more. A veterinary visit is recommended. Good luck.

Thanks for reaching out about Cher and including photos. It does appear as if the right eye is enlarged or protruding. Causes of this can be air entrapment behind the eye (usually a result of a faulty pump), retro-bulbar infection/mass or other systemic illnesses. Test and correct water parameters. A veterinary visit for antibiotics is probably the best advise now. Good luck.

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.

It could be "pop eye". This can be caused by infection or trauma (aggression or from tank furniture). Treatment will include medication and maintaining pristine water quality. Goldfish produce a larger than average bio load (wastes) which can quickly overwhelm a tank and filter. Ideally, one goldfish should have 20 gallons of water and 10 additional gallons should be added per extra fish. The filter should be rated for at least twice the volume of the tank. Check water chemistry using a home test kit or by submitting a water sample for testing. Most pet stores will do this for free or for a small fee. Aim for 0 ppm ammonia and nitrites with a nitrate level of 20 ppm or less. Partial water changes can be done to stabilize chemistry and maintain water quality. Use only aged or conditioned water that is temperature matched to prevent stress or shock. Goldfish are cold water fish and do best between 65F and 72F. A broad spectrum antibiotic can be found in the Aquarium section of the local Petco. These include erythromycin, tetracycline or kanamycin. Brands include Kanaplex, Maracyn , FishMox or FishCillin. Follow label directions carefully and remove the carbon filter insert during treatment if indicated.

Thanks for reaching out about your fish and including photos. Don't think it ruptured as these usually collapse. Corneal bleeding can be due to trauma or ruptured blood vessels from disease. Check and correct water quality. A veterinary visit is recommended to assess and establish a diagnostic/treatment plan. Good luck.

It looks like it could be popeye. This is caused by a bacterial infection. Keep him quarantined, maintaining pristine water quality. You can use Maracyn Plus or similar product to treat. Find it in the aquarium section of the local Petco. Follow label directions carefully and remove the carbon filter insert during treatment if indicated.