Yes, I forgot to add that I use some selcon in the garlic once a day to give the fish a little boost.

Do you have any cleaner shrimp? I just had an outbreak and my sailfin tang was smart enough to avail himself of the skunk cleaner shrimp cleaning station.

ick
 

i am using garlic. looks like the ick goes away and then comes right back. been going on for about a week. i just want it to go away for good.

There have been some good suggestions here already. In order to get rid of the parasite permanently, the fish (all of them) will need to be removed to quarantine and treated (as already mentioned, so I won't bother going into detail).

Having said that, and like it's already been mentioned, that's not necessarily necessary. I have had several fish which seemed to have very minor cases of ich, but with a healthy, varied diet, as well as fostering a community of fish that complement each other (not placing extremely aggressive species with more docile, "community" species, etc.), these symptoms should not continue to reappear.

What are all the other inhabitants in your aquarium? And can you give some more details of your system?

Are you stopping the garlic treatment after you see the ich go away?
You must continue the garlic treatment until the ich does not return.
As mentioned add selcon from time to time and buying a cleaner shrimp is good as well.