What is this?


Reefing newb
Can anyone take a look and let us know if this is a good or bad thing. Couldn't find anything that looks similar on the net.

It seemed to be crawling out of a hole in a rock and eating the coraline algae off the nearby rock.

Just for safety I removed the rock it seemed to be coming out of to the sump. Can anyone help.




Some type of worm. possibly bristle?/ need better pic's. Unless you can definitely identify it as safe I would not chance it and get rid of it, but, do try and get a positive id before you get rid of it.
It didn't look like any bristle worm we've seen. This worm seems to have no legs or anything bristly on it's surface..it is smooth. It elongates itself when feeding on coraline algae. The worm never left the confines of the rock it was stretching from. It has black rings around the translucent body. Very tiny critter and hard to get a good photo of.
well probably better to follow link fishman posted. picture is just not clear enough. let us know what you determine it is. or better pics. try and see if you can observe it after lights are off. use a red light. good luck. ill post if any other thoughts. like Medusa worm/sea cucumber cant tell but another area you might consider.
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possibly a spaghetti worm or maybe peanut worm.either will eat detris.you can try some tweezers or long nose pliers to remove it
Thanks so much for the info.
I checked out the link and after looking at so many pictures of worms found one that was exactly like the worm in our tank. They said it's a peanut worm.
Glad you were able to identify the worm. couldnt get there with the pic provided. anyway a good worm for the refugium and most likely a detritus feeder/desposit feeder. good luck.