as bacteriophage use in industrial application grows there is a need for commercial quantities of identified bacteriophage . this invention discloses a continuous flow bacteriophage proliferation process that can provide commercial quantities of desired bacteriophage in concentrations suitable for industrial use . host bacteria and virulent bacteriophage are fed into a reactor vessel where the phage attach to , infect and lyse the host bacteria providing multiple replications of it and coincidentally concentrating the phage .