I just found a huge worm in my overflow. I was hoping someone could help me ID it. I don't want to get rid of it, if it is beneficial to the reef or sand. It retracts into itself (weird). Fully retracted it is about 3.5" long and about .5" thick. When it extends it is about 7" long, fat on one end and thins out at the other end to the thickness of a pencil line. It looks like a night crawler until it extends. As it extends, the fat end stays tan and the thin end has brown stripes around the body. Has anyone seen one of these? If so, good or bad. Thanks for any help you can give. You just have to love the incredible world of aquatics.