Snapping noise - driving me nuts!!!!!

[reef bound]

We've had our 180g up for about 10 months, and even now, after a thorough search of the rock we originally put in, we still are finding little critters like crabs and little pistol shrimp and little mantis shrimps (I think). They must have been miniscule when we first got them because the ones we are finding lately aren't very big at all. Pistol shrimp is now about 3/4" and mantis was only about 1/2". Found a nasty little box crab about 2" that I'm sure was eating my zoas. And yes, we still have the clicking, too. Moral of this long story, even when you think you get the noise-maker out, you'll probably have another one or two in there. Good luck with the hunt.