Weird String like creature
 

I'v had my live rock and live sand in place (letting the tank cycle) for about 2 weeks now. As of yesterday I noticed a strange creature attached to one of the rocks!

It is about 3" long, black, with very small spikes running half way down it. It is string like!

What the heck is it?

I googled it but nothing came up. Any help would be appreciated!

Thanks,
Justin

Most likely a Bristkle worm. The tank is cycling right? So your live rock shall be cured at the same time. By the time your tank cycles all of the little animals hidden in the live rock shall have died off.

I think it's going to be a difficult ID without a better description or pictures.

Keep googling things like salt water worm, nudibranch, sea cucumber, etc..