For Ich cure in an established reef tank, Paul B and I have the same attitude. Provide a healthy enviroment and encourage a good slime coat to optomize the fishes immune system. Garlic should encourage appetite. Feed your tank inhabitants differrent healthy foods. Neither Paul nor I quarantine. Last Christmas, I got my second ich outbreak in 45 years on a newly introduced Hippo Tang. I used garlic to encourage appetite and added Prime to encourage slime coat. I also added a 70W UV sterilizer to the 75G tank which has been set up for 12 years. I can assure you that any ich that went thru that sterilizer was dead when it came out. However, the life cycle of the ich parasite has several stages that does not include free swimming in the water column. When the parasite is imbedded in the fishes slime coat it is immune to treatment, including cooper. Also, when the parasite leaves its host, it can lay dormat in its cocoon for quite some time. Most literature says 28-56 days. I disagree with this. My first ich outbreak was in a large system that saw no introduction of inhabitants for 18 months. Following a power loss that stressed the system, ich was every where.
Recently on this forum, Paul B wrote a thread on healthy slime coat and fish immune system. Feed your fish a healthy varied diet including as much live food as possible.
Good luck with your ich.
Patrick