where did my mini brittle star go?

[Reefyyy]

hey i used to have a very small brittle star that was a hitchhiker in one of my coral stocks. i kept it and it was doing well for a couple days then disappeared. it was a mini one so it ate detritus and just in case i would give it some phytoplankton time to time bu then it disappeared. suggestions. I'm also not sure if it was healthy from the start because it was a hitchhiker. there is nothing in there but coral so nothing could have eaten it. even open doing a 100% water change when starting to set a whole new structure in my tank i did not find it! it just vanished!

 

[NISMO703]

Probably in your rock work or crevice. I find them in my tank under corals, in powerheads when I’m cleaning them, on my frag rack ect. When you put food in the tank try to look for little arms stretching out.

 

[Reefyyy]

Probably in your rock work or crevice. I find them in my tank under corals, in powerheads when I’m cleaning them, on my frag rack ect. When you put food in the tank try to look for little arms stretching out.

but thats the thing at the time there was no rock only a couple shells which the corals where attached to! I'm so confused! i don't think it is alive anymore and it could not have been in the coral because we recently felt with a pest problem and dipped everything.