identification help
 

Hi all,

I decided after a couple weeks of my hammer coral looking irritated and not fully opening even after trying to move him to a lower flow area, a shaddy area and still no response I dipped him in coral Fx.
I cant be positive this came out of the irritated side of him or off the small piece of rubble that he is attached too but I am not sure what it is. It looks like some sort of shrimp so I assume it is reef friendly. Can anybody identify this?
Hopefully this is what was bothering the hammer but I guess I will find out in the next few days.

Is this just a big Amphipod?