there isn't a whole lot of info about QT'ing coral because a coral QT really is just a 2nd temporary (usually) fishless tank. there aren't all the hoops and hurdles that goes with QT'ing fish.
I personally QT all my non-Fish (coral, inverts, rock, etc) for 3 months before moving over to my DT.
I always dip with interceptor and revive prior to putting into QT. i used to dip on the way out to the DT too, but got lazy on that part... low risk anyway since i have observed for 3 months also anyway.