Found something weird..

[geopod]

I was looking in my tank tonight and noticed something with long strands of white.Looks like a spider web.It isnt a spaghetti worm as I have lots of those and know what they are.I used my finger to touch it and the white strands all sucked back into a rock these strands of white reach out about 6 inch or so.Anyone kow what they are and is it bad for the tank??I will try to take a pic but I dont think I can do a macro shot ....

george