This is one of three Blue Reef Chromis that I have in QT. They have been in for 3 weeks and are coming to the end of Cupramine treatment (tested at .35). I originally began copper treatment because one fish had a white salt-grain sized spec on its right fin. I can see now that it is definitely not ich. It has gotten larger and morphed into more of a rectangular shape. None of the other fish are showing any symptoms of disease. Is it something that I could treat with Prazipro or Paraguard? I don't want to randomly medicate until I know for sure what I'm dealing with.