What is this creature in my tank?

[laurab6320]

Hey guys,

I have a 300L salt water tank that is currently housing live rock, about 5 corals, a cleaner shrimp & a star fish. We had to put our fish in a spare tank as they got a bad case of ich.

The tank has been fish-less for about 8 weeks, and all these creatures are coming out of hiding! We have an influx of snails, but when I turned the lights on today this guy (pic below) was in our tank! I've never seen anything like it before. Any clue what it is? Should I try to remove it?

[Reefer54]

its an urchin....nice hitchhiker (assuming that it came on the live rock) I wouldnt say its good for a reef tank, but it certainly shows how much life came on your rocks.

[devimik]

Looks like a rock boring sea urchin to me. Some like to keep them, but they do eat coralline algae and can be bulldozers - knocking over stuff in the tank. Cool hitchhiker though.

[33mm33]

Nice looking urchin. If you have an acrylic tank I would personally take the urchin out. May scratch it up.

[laurab6320]

Thanks everyone! It's now hiding again. We haven't added any live rock in about 9 months, so it's done well to go undetected all this time!

[AwwNuts]

I have one of those Pencil Sea Urchins in my tank and like it. I have tons of Coraline algea on my tank and it really has not ate it so far. One nice thing about this is that it super cleans flat surface on rocks so if you have a build up of colored gunk it will be completely remove in no time.

They only come out at night and they also eat any dead skeleton of what once was a coral. I have it in an Acrylic tank and so far no problem.