Yep...it will cure Ich. It will also kill every tiny critter in the sand and rock. Which will throw the entire tank into unbalanced conditions. You can't do hypo in the display. What size is your display? How large are the fish you are trying to save?
I had a 90g that got ich. The fish were too many, and too large for a hospital tank. I used "Kick Ick" because I had inverts, and it said it was safe...well the inverts looked awful, and it didn't cure anything, the ich was still there.
My solution: I got some skunk cleaner shrimp (they like to clean up, and eat ich parasites off of fish), I started soaking the fish food in FRESH garlic juice before feeding (to up their immune system). The water was kept at the warmest temperature (85), this made my Hypo tang happy and healthy. His stress caused new outbreaks, he liked it warm and toasty. The rest of the fish were healthy enough to endure, and not be overcome by the parasite. I added no new fish, since all new fish are stressed, and stressed fish can't manage to overcome it, all new fish were doomed for an outbreak, and that would allow the parasite to breed by large numbers, which would even kill the fish who were doing well under the circumstances.
I didn't lose a single fish to ich, they were itchy and unhappy for a long time...because even a water change stressed the tang (which is why I eventually upped the temps) Once the temp was at 85, the tang did better, and outbreaks stopped..
I had to move my tank after two years, I was braced for an outbreak, but it never happened. Once I was sure nothing was going to happen. (using a quarantine tank) I added a new fish, all was well, and I never had ich again. Always using A quarantine tank for new fish, is the only way to prevent ich. An ounce of prevention is worth a pound of cure.
