Spikey Worm Thing ID!!

I have one off these in my live rock and it always goes back in when i turn on the light. 8)

 

Why Are they bad do they go after corals or something???

 

Oh come on mission, EVERY hitchhiker is good, isn't it?! ;-)
Serpent stars are typically reef safe, they will not harm corals or the like BUT a few such as the green serpent a.k.a the "green death" are ambush predators and will either hide under rock ledges then drop on unsuspecting prey(fish or shrimp) or they will make themselves into a "tent" and when a slow fish or invert goes underneath them they drop on them making a quick meal of your potentially prized specimen.

Its a tough call on getting them out. If you wnat to try to trap him, go ahead them examine him. Try to see what he looks like to see if he is more likely going to be a model citizen in your tank or a fierce predator!

Happy star catching!

 

are they common hickers

 

that is a bubble tip brittle star. it should NOT eat fish. its reef safe. i paid $16 for mine. good catch!

EDIT: they are scavengers and will go after uneaten food. mine will actually eat outta my hands.

 

Great I have a monster brittle star in my tank. I also have an enormous serpant star. I've never lost anything, but now I'm worried.