Sounds like it could be either Costia or Chilodonella. Try quick cure for a treatment. Follow the instructions on the bottle. You could also raise the temperature to around 80 degrees F. If it is Chilodonella your fish may die from the disease (it breaks down skin and gills). If you raise the temperature, I would add an air stone to add oxygen (as warmer water holds less oxygen), and since your fish is already stressed the additional oxygen would probably help. Keep us posted.
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Phishie
Site Coordinator

"An ounce of prevention is worth a pound of cure."