The biopharmaceutical industry has established and increased the use of single use systems in all unit operations in order to fulfil regulatory requirements and high quality product standards. Single use production equipment is particularly important in bacteriophage production, due to the lowered risk of cross contamination, simplified cleaning and sterilization validation and increased flexibility in production line layout, necessary when producing multiple bacteriophages for tailored phage cocktails. Foam formation is a challenge in bacterial fermentation and particularly in phage production, and has been a hurdle in the development of single use bioreactors for bacterial fermentation. Here, we present a single use bioreactor with a passive foam handling system, free from chemical or active mechanical anti-foaming measures. The bioreactor is scalable and suitable for high density production of bacteria and bacteriophages within the regulatory requirements for food additives and biopharmaceuticals.