I do not have any experience with ich. The fish in my system are not really ich-prone (a melanurus wrasse, a clown, and a ywg). I am thinking of getting a tang, which are notably ich-prone fish. I must start off by saying that I am not asking whether or not to get a tang. I am also not asking whether my tank is large enough for a tang, or how likely a tang would be to get ich in my tank. I am not looking for a debate here lol. Here is my concern. I am very against putting chemicals in my tank. There is absolutely no way that I would ever put a copper-containing medication in my tank if ich did become a problem. If I did go ahead and get a tang, and this tang eventually got ich, would this make my other fish more vulnerable to the disease? Even though they aren't prone to it? What would be the consequences here? Also, how likely is a fish to recover from ich? Can they recover on their own? Would all of my fish die if I did not do the treatment?