What's going on with my ACAN?

[nature786]

This and several others in my Tank are looking like this (pic below).
some advice please.

 

[Tahoe61]

Looks like your losing them.

Trouble shoot
1. Near by corals stinging the acan.
2. Check water chemistry, make sure your not seeing big alkalinty swings. Ca/alk/mag all have to be in line.
3. Too much lighting, not enough lighting?
4. Can you feed it?

 

[nature786]

This one hasn't been eating all though the others are.
No other corals around it.
I have not checked the Alk levels. Shall do so tonight.