Best way to catch/kill a crab?

[Mano]

So I recently discovered a most un-welcome hitchhiker in my 10g nano: A rock crab. I do not have fish yet, but I'd like to look at getting some next week, not going to happen so well with the crab. It's already killing the clams I've had growing so he really does need to get lost. I've tried setting out traps by putting some dried sea weed in a net at the bottom of the tank next to the rock he usually hangs out at, but after two weeks, no luck getting him.

Any suggestions? I'd be very grateful. :3

 

[quaddity]

I had this nasty crab in my tank that started eating corals and I believe killed some fish. I got it by putting in a glass jar (was a salsa jar) with a piece of shrimp in it right by its lair.

 

[Mano]

I had this nasty crab in my tank that started eating corals and I believe killed some fish. I got it by putting in a glass jar (was a salsa jar) with a piece of shrimp in it right by its lair.

Oh I'm going to try that tonight, see if I can get the little bugger. Thank you.