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