We just bought a 90 gal. complete set up a week ago. When transferring all the water with the rock, we noticed a little light blue lobster/shrimp 1/2" long. Because we had nowhere else to keep him, and not realizing what we were dealing with, we slipped him into the tank along with everything else. Not long after, we heard the clicking and one of my blue leg crabs has be dessicated. I found out how to make the trap on
www.saltwateraquarium.about.com and am not trying to catch the little bu#@er !! Please let me know if you have a better way - have been trapping for three days and only catching crabs. Good luck!!