Copperband with Lymphocytes

[LeanneP]

I've had a copperband in quarentine that I purchased about a week and a half ago. A few days ago I noticed a spot on his tail fin which I think is lymphocytes. I know it is a virus and there is no treatment. Has anyone had experience with this? I am just a little worried about putting him in the display tank eventually if this is something that could come back again and affect my other fish. I have never had any diseases in my tank so not sure if I want to introduce this and have my other fish catch it.