Ok, so if there is 1 affected fish, and after 24 hrs of first appearance, there are no other cases, couldnt the affected fish be moved to quarantine, until the parasites dropped off the fish, then the fish, mnow healthy is moibed back to the Display tank.
I thought it could also infect the live rock in the tank and harbor in there if you don't get the fish out before the ick falls off
It can "infect" the live rock. It's not really an infection per se, but rather the trophots lay in waiting in the live rock and substrate until they break open into free swimming tomites. At this point they can re-infect the fish. Once one fish suffers a major infection, it starts a chain reaction that expoentially increases the number of bugs in the system, causing healthier fish to be overwhelmed and themselves become visibly infected.
The single biggest misconception about Ich is that if the fish doesn't have spots, its not infected. While it is possible to have a completely ich free system, this is not true in 99% of the cases. In almost all systems, ich is always present, but the fishes are not stressed and are therefore able to reject a major, visible infection.
Therefore, simply removing the infected fish until the trophonts fall off does not eliminate it, though it may solve the outbreak. The only way to completely eradicate ich from the system is to do one of two things:
1. Treat the system with copper or hyposalinity. These methods actively kill the ich, not just stopping it from attaching, etc.
2. Remove all animals from the system and allow the system to go fallow for 30 days or so. All ich bugs will die in this length of time.
In most cases, however, completely eliminating the ich from the system is not viable. It's can always be a dream, but the trick to stopping ich is to have stable water conditions, a natural, non-stressing environment for the fish, and to make sure the fish are not overcrowded or oversized for the tank.