A mantis? No, a snail!

[Limbo]

Ok, here is the story. I got live rock about 2 1/2 years ago and a mantis was good enough to come along with it. I managed to remove the mantis and set him up in a dedicated tank.
For 2 years I continued to hear "clicking" in the main tank. Another mantis I thought. Never saw it, never had any of the tell tale signs.
6 months ago I moved to a new tank. I "starved" the tank after the fish had all been removed, used a bait trap..... nothing. Took all the rock out and inspected it..... nothing.
By this time I was thinking I was just going crazy.
So up goes the new tank. In goes the old rock..... and in goes the "clicking".
Then one day while staring into the tank, about 1 inch from the glass (as I'm sure we all do), I noticed a Astrea snail, sitting on a rock, bouncing up and down. Each bounce was a click every time its shell hit the rock.... The click I'd been hearing for years, a snail???? The same Astrea snails moved with the rock.

I've observed this numerous times since the first time and laugh to myself each time.

Has anyone ever heard or seen anything like this before? Am I just crazy?

 

[Spiffyguy]

I have a power head that has a Y on it with some loc line. My snails like to get in the right spot on the loc line that they barely touch the glass. It vibrates likes crazy. First couple times I was freaking out looking for the cause. Now I have moved the loc line far enough that they only buzz occasionally.

 

[Jayded]

I had a similar problem with a tank I removed a Mantis from. I kept hearing the clicking and one day I was in the room when it happened and glanced up to see a snail on the glass twisting then letting itself go so as it spun the shell tapped on the glass... odd behaviour but at least I knew what it was now!

 

[Drix]

My Zebra turbo does this all the time, drives me insane!

Course, my tanks are in my bedroom and he likes to do it at night -.-