Fig. 6

Total microbial count (CFU ml−1) measured in water samples from: control, H2O2, and PAA groups at different sampling time: 30 min after treatment, 72 h. before water exchange, 72 h. after water exchange, and last sampling after bacterial injection. Bars represent mean values ± SE, each GP including technical replicates. An asterisk (*) & (**) denotes significant differences between the control and the treated groups (P < 0.05, p < 0.001, respectively).