(A). Potency of drainage effluent from the reactor measured as the ZOI of effluent against S. aureus UAMS-1 reported on a Log2 scale for 48 h after flow rates were initiated. The dashed line indicates the diameter of the disc. When the ZOI of the effluent was equivalent to the diameter of the disc, it indicates growth up to the edge of the disc and is assumed there was no antimicrobial potency. (* p < 0.05 for the CSBv+tplusSpacerv+t compared to the Spacer v+t alone, * p < 0.05 for the CSBv+tplusSpacerv+t compared to the VP, and * p < 0.05 for the Spacerv+t alone compared to the VP) N = 3, mean ± SE. (B). ZOI of effluent against P. aeruginosa PAO1 reported on a Log2 scale for 48 h after flow rates were initiated. The dashed line indicates the diameter of the disc. N = 3, mean ± SE. (* p < 0.05 for the CSBv+tplusSpacerv+t compared to the Spacer v+t alone).