I'm having a similar problem with my colt coral, jammerz (sorry for semi-hijacking!). All other livestock is doing teriffic, but colt looks like it's dying. I'm running carbon just in case, and I've adjusted the powerhead for best water movement (tried several angles). Water readings are fine.
I got the coral the Friday before the 4th of july.
Here's what it looked like a day after introduction to the tank:
And its state now:
It seems to perk up a little in the morning and at night, but still limp, shrunken, and now the un-polyped skin is starting to wrinkle. The polyps extend, mostly, for the majority of the day, but around the afternoon it turns into what is shown above.
I think it may be my temperature. Last several days, it's gotten in the mid eighties, once getting up to 86. What's your temp, Jammerz?
I'm going to kill the light earlier, only giving the tank about 8 hours or so. See if that helps any...