Fish Pop-Eye – Swollen eye, eye bulges out
- Description: Fish pop-eye is a swelling of the eye. The fish eye bulges out in this way because of fluid build up. The symptom is most dramatic when seen from above.
- Possible secondary symptoms: pale color, apathy, loss of appetite, ulcers. The affected fish may isolate itself from the rest of the group. Sometimes also: dropsy (swelling of the abdomen with spiky scales) and eye fungus infection.
- Direct causes: Most often bacteria but sometimes also viruses or parasites.
- Contributing factors: Stress (poor water quality, overstocking, unsuitable diet), injury. Check the water quality: it should have 0 ammonia, 0 nitrite and low nitrate. Use a proper water conditioner to eliminate chlorine and chloramine in the tap water. And make sure that water changes are made with water at about the same temperature as your tank. Additionally, check your pH, especially if your water is soft.
- Severity: Severe. It is necessary to act as quickly as possible to optimize the chances of recovery. Placing the affected fish in a quarantine tank is recommended.
- Pop-Eye Treatment: Commercially available antibacterial treatments – API Melafix, eSHa 2000, Sera Baktopur, Interpet Disease Treatment – or veterinary prescription (antibiotics).

Thank you to pybal for the picture.

Good hygiene and water quality can prevent the re-occurrence of this disease.

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