Automatic membrane-filtration system for the "on-demand" supply of large volumes of sterile medium in continuous culture.

The construction and use of an automated membrane filtration system is described which produces 300 liters per day of sterile medium over at least four months of continuous fermentation. The capacity of the system is limited only by choice of filter type and has applications in continuous pilot plant work or medium-scale batch fermentation, in the bulk supply of communally used laboratory medium, in supplying banks of small-scale continuous fermentors, and for remote control of medium supply in hazardous fermentations (e.g., methane) with great savings in time and materials. Only two sterile storage jars are needed, irrespective of the total demand for the medium.