Abstract: A bioprocessing system for a feed such as wastewater comprises an anaerobic reactor subsystem, an aerobic reactor subsystem, and a recycle loop for partial recycling of the aerobic reactor subsystem effluent. The anaerobic reactor subsystem is capable of providing anaerobic processing of the wastewater in the substantial absence of aerobic processing of the wastewater. The anaerobic reactor subsystem can include a single anaerobic reactor or a plurality of reactors. The aerobic reactor subsystem is in direct communication with the anaerobic reactor subsystem, with the aerobic reactor subsystem being capable of providing aerobic processing of the wastewater in the substantial absence of anaerobic processing of the wastewater. The aerobic reactor subsystem processes the wastewater from the anaerobic reactor subsystem without intervening bioprocessing of the wastewater. As with the anaerobic subsystem, the aerobic reactor subsystem can include a single aerobic bioreactor or a plurality of reactors.