My wife has (thankfully) really taken to the new tank. She was watching the tank really closely this evening and exclaimed, "Eww! What's that bug?" "Bug?" I asked. "Yeah, there's a little bug in there." She said she saw a tiny "bug" crawl out of of a piece of live rock, scurry down the rock and into another little hole in that same piece of rock. The holes she pointed out were no bigger than a big pin head, so this is a small critter. In describing it, she said it was one shape - not segmented. That it had legs - "at least 4," and that it was tiny, "like a little ant or bug." So.... What could this little critter be? I added some live rock a while ago - maybe 5 weeks ago. I assume this, whatever it is, came along as a hitchhiker? What do you think it is?