personally, i dun like chemicals...so i will choose not to add watever ich-medi there is in the market...
wat i do is feed feed and feed...if they are eating, this method will ensure that they get fatter and stronger...
i feed up to 4 times a day...small serving each time to ensure that they will eat and no food will be left on the sand to rot...
if they are on pellets or flakes, it should be sufficiently nutritious...if they feed only BS or mysis or other stuffs, soak with garlic guard 1st, or garlic extreme will be good..