From time to time they get a little ich... just try to keep water temp and parameters stable... If he has it bad, there might be a bigger problem.. I find running a good uv light almost a necessity when your temp can't be kept as stable as this fish needs it too be by using a computer with a probe...
I am having the same problem right now also. Dont sweat it. It can be fixed. If you can pull the infected fish out of your tank and treat him. PM me if you cant we can firgure a way to fix him.