I recently have decided to remove ALL my hitchiker crabs.I had two,that I know of,that I am getting out.I caught one and have one left.I had an sps crab that would visit the two sps each night.He would travel from one to the other.Well,one of the hitchiker crabs moved up to the spot and ambushed the sps crab and ate him!I had no problems with the hitchikers until this.I wish I had taken them out when I had the chance in the past.All crabs are oportunists and will jump at a meal anytime.So,I will ban them to the sump to duke it out with each other from now on.