Ok another status update:
Since my outbreak the following fish have been added to my system. Some to my 120 but most to the 300. I didn't treat them with copper in my qt tank. I slowly introduced them to my system water for 3+ weeks before adding them to the system.
Yellow Tang
Clown Tang
C Blue Tang
Leopard Wrasse
4 Purple Queens
Pencil Wrasse
I am happy to report all fish are healthy and showing no signs of ich. With that said, here comes the real challenge. I just purchased an Achilles Tang. He has been at the lfs for 3 weeks, eating well and has good weight. I added him to the qt last night but knowing this fish I have decided to stop the flow from my system to the qt and isolate the qt tank. I will do 20% water changes using system water every 2-3 days and monitor the fish. Again I won't be using copper for treatment. I will keep everyone posted. After 3 weeks of qt and IF he shows no signs of ich I will slowly bleed him in the system. I'll give him a good month in qt before going in the 300.