Well I was going to get it but for my tank its $50 a bottle
Before you spend the money, please jump over to Reef Central in the Disease Forum and read the stickies posted by Steve Norvich (Snorvich) as this parasite has a well documented life cycle. There is tons of information written on what works, and 3x as much faulty info floating around about how to "manage" Ich.
If your fish has ich, then your system has ich as well.
If you want to cure it for good, you need to QT the fish with Hypo, Cu, or Tank Transfer method and let the tank run fallow for 8 weeks.
It sucks, but I have "been there done that" and re-booted my 180 system last year after a horrible outbreak of Ich. I treated the survivors for 4 weeks with Cupramine at .4ppm, left them in a QT tank for an additional 5 weeks and ran the 180 empty to starve all the Ich because there were no fish hosts.
I know many choose to add cleaner shrimp, Kick ich, cleaner wrasses, UV, etc.....all of which are a band aid.
What you see a cleaner shrimp picking at is actually the scar tissue after the parasite burst through the epidermis of the fish. The parasite is already burrowed in the sand waiting to hatch hundreds of new tomites to infect your newly added and stressed fish. UV is fine, but it only kills what runs through the filter.....the parasite lives in the substrate for the most part and since fish sleep in the same spot every night, that is why they tend to wake up infected and in worse shape than when they went to sleep.
If you wish to keep any of the tangs with a drier skin and less protective slime coat, you will likely see the parasite on your fish as the life cycle repeats unless you treat it for good. You may see the symptoms disappear as the life cycle progresses, but you are only a power failure, new addition (IE- Stress), or other trigger to cause a massive outbreak.
Education about this parasite can save a lot of heartache (and dollars) in this hobby. Hope the links on RC help.
Larry