I have had some fish cured in 3 days, some in a week or so. I think it all depends on the type of fish, water conditions, and how far along you caught it.
there all seemin pretty much better already all lookin like happy fish with white dots now except ciaphas who im sure keeps dying till i poke him then it awakens him from the ded. he sits there not moving for hours.
Keep treating after the spots go. Cause its a parasite it has a life cycle, most of which you cant see. You need to treat for about a week to get the whole cycle
I had quarentined one of my neons for ich on friday, and today he seems to be doing much better, the spot is gone, but now a couple of my other fish in the community tank has it, so I am starting a treatment for the tank. I hope it will go away ina few days like my other little guy.