Mantis?

[justinl]

the clicking may have been from a pistol, or a snail in front of a powerhead whose shell is hitting the glass, or of course the mantis. Organisms that are newly introduced are often skittish and nervous so that may explain the cleaners. If you want you could throw in a bottle trap to see if you could lure out the mantis if you have one. Have you done the stake out? some mantids are diurnal (active during daylight) and some nocturnal so you'll have to watch day and night. A visual/pic is the only solid proof.

What was the fate of the last one? you didn't kill it did you?