Dying Bubble Coral or...?

[Dinkins Aquatic Gardens Verified Sponsor]

Just an hour ago all the polyps were fully inflated, but now there are bare spots. No skeleton showing though.

Is this tissue recession or maybe the pumps just blowing the polyps around, creating spaces (the pumps ramp up and down).

P.S. He went to bed (withdrew his polyps) so I turned on the lights to get a clear shot of good skeleton. Not happy with all the brown stuff on the spines of his skeleton? Any ideas what's going on? He had a huge string of brown hairy stuff coming from him earlier but my new tangs made quick work of that.

 

[vetteguy53081]

Sudden recession. was there any chemicals just added to tank ?
If auto-doser, did it malfunction?

General causes are:
Alk spike
low CA
low salinity
High temp
Too much flow or light

 

[Dinkins Aquatic Gardens Verified Sponsor]

Thinking it is high flow and high light... It was at the top of the tank. I've moved it to the sand now. I did smell the coral and it didn't have any odor, so hopefully not BJD.

 

[Nburg's Reef]

They like low flow and tend to do well in low light. I’m thinking it should be okay as they are pretty tough corals