A biogas plant fermenter supply method increases total throughput of substrate through fermenter chambers while not changing the number of fermenter chambers. An inoculum fermenter chamber is supplied with raw fermentation substrate and fermenting for a dwell time, returning part of the substrate fermented in the inoculum fermenter chamber in the form of a self-inoculating substrate to the inoculum fermenter chamber by a return path, the part being mixed with the raw fermentation substrate, and supplying a fast fermenter chamber coupled to the inoculum fermenter chamber with an additional part of the substrate fermented in the inoculum fermenter chamber in the form of a fast fermenter inoculation substrate and mixing the additional part with fast fermenter raw substrate of an amount per unit of time, wherein fermented output substrate is removed from the fast fermenter chamber after a dwell time of the substrate mixture introduced into the fast fermenter chamber.