How to trap a crab

[Cadu]

Hi Fellow Reefers,

So I have one Xanthidae Crab and 2 Mithrax Crabs that hitchhiked in the LR.
Is there a better bait to use in a trap to catch them ?
Any ideas of a DIY trap or better buy a commercial one ?

Thanks !

[mbbuna]

take a small drinking glass and place it in the tank with the open end up but next to a rock so the crab can climb the rock and get into the glass. place a piece shrimp or fish in the glass. the crab will go into the glass to eat the food but wont be able to get out