wrote in message
...
columnaris typically attacks the mouth, white threads around the mouth is
nearly
diagnostic. in fact, it is often called "mouth rot". Ingrid

Not to nit pick...well OK exactly to nit pick...the OP never mentioned
anything about threads or mouth damage, aside fromt the one fish that had
it's "face eaten off". Would it not make more sense to take a dead fish to
the vet and get it tested before you begin dosing for a disease that you are
not sure of?

BV.