I'm not sure what people usually do as far as soaking, but no way would I soak overnight. When I have soaked my snakes for stuck shed I left them in until the water temp dropped to 80. You have PAM, and that's what really matters. If the infestation is really bad you could get some reptile relief, you can put that on your snake. Soak your sake for 15 mins or so, clean the tub, spray the tub-let it dry, spray everything around the tub, and spray the doorway to your quarantine room. Then you need to take care of the snake room, take everyone out of their tubs and out of the room, spray the doorway to your snake room and the rims/holes on all the tubs. Let the tubs dry and put the snakes back in. That should keep your healthy snakes safe from becoming infested. Good luck!