What is this worm?

[Daddy-o]

I have found dozens of these little guys buried in my sand. What are they and do they cause harm? How do I get rid of them?

 

[jrcordero4]

Bristle worms. They are good for your tank as long as they don't get too big.

 

[Daddy-o]

There are actually a few large ones - 3"+. How do i get riding them? Do they harm corals?

 

[jrcordero4]

Take a look at this thread. It will give you some varying opinions on bristle worms.

 

[jrcordero4]

http://www.3reef.com/forums/inverts/bristle-worms-good-bad-86930.html#.UxJFjSm9LCQd

 

[mr_X]

Common bristle worms don't harm anything, large or small. If you have large ones, I would say there's plenty of food available for them (you are overfeeding). These are scavengers that eat poop and uneaten fish food. They will never touch anything that's healthy. Reports of them eating corals or fish are because the corals were failing, or the fish was dying/dead, and they just got caught in the act with the "smoking gun".