My female betta has a white ring around her eye. Is it popeye?

'Popeye' syndrome can have different causes including infections and poor water quality. In your case the other eye may be become affected very quickly. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. High ammonia levels, PH imbalances may be responsible for that. Oxygen concentration (this could be one of the main causes as excess of O2 can cause it very commonly) and quality of the filters should be determined as well. If water quality is good and there are no major imbalances, your fish should get examined to look for any sign of bacterial/fungal infection and eventually water should be treated. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.

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.

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 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 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.

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.

This could be a fungal or bacterial infection. Less likely is a parasite. Maintain pristine water quality via filtration and regular partial water changes. Maintain water temp between 78 F and 80 F. Consider a broad spectrum antibiotic or an all-in-one type treatment. Either can be found in the aquarium section of the local Petco. Follow label directions carefully and remove the carbon filter insert during treatment if indicated. You can also add in some plain aquarium salt (NOT table or Epsom salt) to reduce stress, improve gill function, treat minor infection and aid in recovery. Dissolve up to 1 teaspoon per gallon of water. Salt can be used in conjunction with an antibiotic or other treatment.