ID on a Worm

I have a 55-gal SW FOWLR tank. I am trying to figure out what kind of worm is in my tank and if it's bad. They must be breeding like crazy because they have multiplied within a couple of weeks. The worm is completely white in color, about 1-3 inches in length and as skinny as a width of hair. If anybody can give me any advice on what this worm is and where it came from, please doo! Thank you!

--Trev

Sometimes it will move across the glass in a zig-zag motion, very strange. Sorry can't get you a pic., but thanks for the help.