Help me to identify this creature

[Alex33324]

I just received my 2 boxes of Walt smith live rock at the bottom of the box was an invertebrate that looks like a worm or a sea cucumber it moves and change lenght its thick in one side and thin at both ends its color its mid to dark brown despite being smooth in appearance the feel its rough like sand. I do not want to kill an innocent creature nor want to keep a pest in my new tank I know I should provide a picture but I was not being able to take it. please help me find out what it is, as soon as I can I will provide a picture of it. thanks for your feedback

 

[wliang]

Pic needed.

 

[Sk8r]

The two things it is most likely---a peanut worm or a cucumber---are both beneficial, though some cucumbers if they die can release a toxin into the tank---if healthy they're safe. If it should die in your water stream, run carbon and a lot of it.

I have never personally handled a cucumber, so I can't tell you what they feel like. The safest place to keep an Unknown Animal is in your sump while we try to id it.