A method for blow molding and filling sterile containers (T) of preforms (P) in a container treatment device (V) containing a blow module (B), in which the preforms (P) are transferred from a heating device (H) to the blow module via transport devices (3), and the containers (T) are transported to a filling machine and filled, where a sterilization treatment is performed each at the preforms (P) and the containers (T), a main sterilization treatment is performed at the preforms (P) between the heating device (H) and the blow module (B), and only a subsequent sterilization treatment is performed at the containers (T) on the transport path to the filling machine (F). Further, a device having a main sterilization module (HS) between the heating device (H) and the blow module (B), and a subsequent sterilization module (NS) between the blow module (B) and the filling machine (F).