Yellow creature question

[FrankieBones]

I have a few of these in my tank. I never see them on coral. My guess its some type of cucumber species. Anyone have this or have a clue what this is. Thanks

 

[Loose tenticle]

Nudibranch?

 

[marrone]

It looks like the common Yellow Sea cucumber. A big clue into what it is would be if you see the feeder tentacles on the front of it.

 

[FrankieBones]

Thank you... I was like 80% sure. I do have a good amount in my tank. They must be reproducing.:division: