need to catch an emerald crab....

[jess128]

as most of you know I am taking down my tank and selling everything. I have an emerald crab and a potential buyer, but I cant find the crab! I wasn't sure if he was even still alive cause I hadn't seen him in months, and I tore my rock apart and still no luck. then my little brother told me he was him one night and the sucker burried himself in the substrate. I looked up traps in these forums and the only good one I could find was the inverted bottle idea. Problem is, I think my crab is too big to get himself inside the little opening in the first place. Any ideas?