It's decaying flesh of the coral. An entry point for scavengers.

If the concensus is that it's a gonner, I'd start digging

Maybe you'll even find something under the flesh on the top side

Good luck Jess

As a last resort, you could try removing it and placing it in an iodine bath then in a separate tank with no substrate.
As long as it's on the sand the scavengers still have free access to it.

That could be possible , I'm using caribsea seafloor special grade , this tank has been set up for two months and was transferred from my 90 which had sugar fine sand which was a much finer sand.

The scoly is not looking good , the holes are getting bigger and the skin is just falling off now.

Your beautiful red and green scolymia! Must be the Grinch trying to steal your Christmas :(

Just seeing this now, that's terrible Jess! I realllllly hope this pulls through, it's very unfortunate that these are unable to be fragged
Must be some sort of worm or parasite that was eating the flesh and caused an infection boring its way through. I think of this as like a flesh eating disease, unless the dead flesh is taken out of the equation, it would seem probable that it will continue to spread.

Do you have a syringe capable of blasting tank water with some sort of dip at decent pressure to blast away any loose dead flesh and hopefully also chase the problem out of its burrow? I can bring you one if not

Final result its a goner ! http://img.tapatalk.com/d/13/12/16/tu5y5a8a.jpg

It's sitting in a dip of coral rx and I'll tear it apart in the morning to see what I can find as my son just woke up and started throwing up so I have to look after him. I did find a few more small worms that came out when I first dipped it and pulled the loose flesh off.

Sorry for your loss Jess such a nice piece hope everything else in the tank is doing good Ryan

Thanks Ryan

Sorry for the loss too Jess :(
Don't throw it away just yet!.. If you're thinking of tearing it apart tomorrow, at least leave the center around the mouth in tact. Place it in a shaded are of your tank and give it a week or 2 and see if there is ANY sign of life around the mouth. If so, there may be a chance for it yet...