Amphipod-ish critter bored into my GSP?

[Jcon82]

Hey All,

Was doing maintenance yesterday and notice one of my newer frags of WWC GSP was all closed up on the frag rack. I was picking algae so I grabbed it to pluck a string off and saw critter wiggle under the gsp mat. Now I do have bad luck with GSP but this frag was super healthy up until now. The creature was big enough for me to grab with tweezers but my clowns snatched it before I could take a pic.

Based off the ID thread it looks like a big amphipod. Are these known to irritate corals? Also will mandarins eat them? I just added one so the issue may already be gone

 

[GHOSTLY]

I've seen my mandarin eat larger amphipods but it was really hard for him. He'd rather go after copepods or super small amphipods