Just a bump, but I have to have a sarcastic/humerous comment
Its probably one the aptasia factions in your tank, creating the new and improved subway system for your HUGE tank.
75g w/ 30g sump, 160# LR
, 60# sand: Inverts =18 turbos, 30 nassirus's, 40 blue leg's, 5 emeralds, 1 CBS, 1 skunk cleaner, 1 brown gulf shrimp? and various other LR
hitch hikers yet un discovered or un-ID
Fish=1 yellow tang, 1 yellow headed jawfish, 1 pink/blue shrimpgoby, 2 perc clowns.
Future fish = 1 sixline, 1 lawnmower blenny