that's what I'm guessing too, although seems to be the only coral affected by the Alk swing.
I got parameters back in check in mid December. No luck with the torch so far, so it needs to go somewhere else or it will die. Showed some more skeleton today, but I did manage to feed it a bit. It opened it's mouth after target feeding some oyster/roti/pac pods/arcti pods/phyto feast soup, so it's not completely gone.