What is this tiny (1-2mm) worm I found under a small Acan frag?

[merkmerk73]

Heres the worms dead in a dip. They’re extremely tiny - just 1 or 2mm at the most.

I found them under my Acan frag - just a few - when I picked it up to move it after it started behaving strangely.

(also not sure why this Acan is shriveling up - maybe some folks have some thoughts on this too as a bonus? One pic happy and fluffy, then over past several days it’s been shriveled in some kind of feed mode or maybe defense)

 

[merkmerk73]

Anyone have any ideas?
This acan continues to be unhappy

I did find hydroids growing on the stony part, but I’m still curious what those tiny worms are