A few yrs back,my female Tomato Clown got a mild(10% of body had white dots)case of ich.She was in a reef tank and i didn't want to break it down to put her in a hospital tank.What worked for me,was feeding various kinds of good(read the label on your foods;look for lots of vitamins,minerals,spirulina algae,etc..)foods 4-5 times a day.Another thing i wanted to try(i heard mixed reports about garlic being effective)was this garlic food treatment.i took a fresh clove of garlic,chopped it finely,then mixed it into some quality flake food which was one of the 4 foods i fed daily.
Within 3-5 days the fish seemed to shake the "white dots" and has been healthy ever since(i've had her 4yrs now)Its purely anecdotal evidence if the garlic played a factor in her treatment.Personally,I think it was the multiple feedings that she recieved boosting her immune system.