Well saw a few critters today, including that worm, a snail, a brittle star for a split second, and what appeared to be a skipper. Wen't out tonight for a bit and turn the fluro's off. When i got home and turned them on, there where critters everywhere, at first glance i could count about 15. There was one coral on the side of one of the rocks that i thought had died today, it turned all black and shrivled up. When i turned the light on it was in full extent and all colourful. Am loving this saltwater tank already, and i don't even have any fish in it.