What is eating my zoas??

[Maddlesrain]

I have not added, or had, any zoas in this tank for many MANY months, so I don't think it's a pest specific to the corals.

Last night I tried a $10 zoa frag to test the waters. This morning the frag plug was stripped bare (so frustrating!!!).

The fish are all damsels, chromis, and a purple dottyback. Are any damsels known to eat zoas?

I have a large coral banded shrimp, several different types of serpent starfish, lots of different grazing snails, and a couple scarlet hermit crabs scooting around. No one really jumps out at me, maybe the shrimp? But I've never seen him pick at any of my other corals ever.

 

[Saltyreef]

If this is the only issue you've had, it leads me to believe the zoa frag had a bad glue job and is floating around the tank behind a rock or in the filters somewhere.
Snails and larger starfish can nudge them loose sometimes.

Quite common in my frag tank.