a Tropic Marin pro coral cure dip will kill them (follow the instructions on the bottle) but I'm not sure if it's safe for hammer corals, someone else will have to chime in on that. As for the worms that are now in your tank.... Providing a pic of the worms would really help in identifying whether or not they will be a pest but I never trust something that arrives in large numbers!! You can order FW exit online.