Cory died:(. I did look like columnaris, but it was too late. Now my other 2 cories acting letargic and one of them is trying to scratch himself against gravel. It is albino cory, I can't see anything on the skin. Is it ich?

Hi everyone, I am new to this site. I just found it trying to find some information about Albino Cory. One of my 3 cories is sick, it turned bright white, was staying close to the surface for last 3 days and this morning I noticed white fuzzy spot on its tail. I noticed that my other 2 cories move ...