Hole in Cyphastrea frag?

[PotatoPig]

I got this meteor shower Cyphastrea a few weeks ago and it just doesn’t seem happy at all. On a closer look at it it seems to have a hole in it - is this some sort of pest or is it dying?

Any route forward?

Parameters:

calcium 400
Alk 8
Mag 1400
Ph 8
Temp 76-77
PAR here: About 70
All other corals (soft, LPS, SPS, and the BTA) are doing fine.

 

[tbrown]

That looks like possible tissue recession or a polyp got but off...

It could be a pest as well, but it looks like skeleton underneath?