The relative flux (J/J0) of the MF membrane with prechlorination at low and high mixing intensities is shown in Fig. 5. A marked difference in flux decline between low and high mixing intensities was observed. A mixing intensity of 600 s−1 delayed flux decline substantially for the filtration, and could have been due to the characteristics of the cake layer as suggested by previous study that cake layer formation determines the magnitude of irreversible fouling [20]. Other researchers have also found that cake porosities are affected by the properties of aggregates such as size and fractal dimension [21]. As a result, mixing intensity during chlorination can significantly affect the properties of cake layer formed by Fe and Fe–Mn oxides in microfiltration.