Hoping someone can I.D. whatever this is on my rock. Just set up a 60 gallon cube and used all dry rock with one piece of live rock i picked up from another member. Tonight I decided to shine a light in my tank to see if any of the critters in the tank were making new homes in the dry rock. I know what brisstleworms look like, and this is definitely not one. It appears to be white/tan with brown speckles, and is smooth. It is stretched out with each end inside the rock, so i cant give a definite length, but what is exposed is a good 3-4 inches. Can someone please let me know if this is a good or bad guy. Thanks in advance, Dan.