quarantine corals?

[Melina]

Hey guys. I'm about to set up my first reef tank in a couple weeks. I know a quarantine tank is a good idea if someone is planning to keep fish and is concerned about ich.. but I only want corals with a couple of clown fish. I mean, 2 fish in a 54 gallon. Is it worth the time and money for me to set up a quarantine tank? How many of you quarantine corals before adding them to your main tank and is it really necessary? Do corals carry diseases that could spread to other corals in the tank? Also, how many of you quarantine sessile inverts? (eg. starfish, shrimp, etc) thanks!