I noticed today the silver dollars seem to be "salted"... so I suspect it is ich although I've not had experience with this disease so far in my fishkeeping. I have other fish in my tank (dwarf gouramis, platys, giant danios) but none of them seem to have the "salt" on their scales... What is the best course of action to get rid of this? FYI, I have a 55 gallon tank. Thanks in advance for the responses!