White flat worm?
 

Came home from work today and saw a white flat worm. It was about 1 cm. I pulled it out. Haven't seen any others. And have no idea where it came from

Are they good/bad.

I did read that they eat red and brown flat worms along with various pods but would like your expertise.

Thanks

Can't help with the reef safe part but been using this link as a guide might help

http://www.extreme-aquatics.com/707/...reef-aquarium/