a The RCCS disposable vessel with entry ports to the front and gas permeable membrane and rotation fixing to rear. Centrifugal force (Fcf) is controlled through rotation speed enabling biomass to grow without encountering the vessel walls. Gravity (g) in non-rotating controls collects biomass to the bottom of the vessel. b M. bovis BCG RCCS-biofilm formed after 21 days. c Heavily corded Kinyoun-stained RCCS-biofilm after 21 days. d Biomass in non-rotating control at the bottom of the vessel after 21 days (vessel agitated for imaging). e Kinyoun-stained non-rotating control with limited cording after 21 days. White scale bar is 1 cm, black scale bar is 20 µM.