One rock I've had for over 2 years now is very much encrusted in purple. I was looking at it closely and noticed that there were several of these things. They looked like 2 small quarter inch hairs hanging from each little tube and these little "hairlike" things were moving across the rock This one rock had several of these. Each little tube had only two hairlike things hanging out. I'm assuming these are just another type of tubeworm. Anyone have an idea? Thanks