I have noticed that one of my very old large Marble Angel fish may have developed Pop-Eye. Not to be confused with the Sailor!
Pop-eye is caused by: bacterial infection, parasite infestation, metabolic disorders, and poor water quality.
Symptoms: one or both eyes swell and project from the head. In severe cases, the eye can burst from the socket.
Treatment/Control: affected fish can be treated with MelaFix.
The water quality in the aquarium checks out okay, I’ll maintain a close “eye” on her condition. Excuse the pun!