“…Iron–hydroxide induced clogging is considered as the most common cause of chemical clogging in MAR (Bouwer, 2002; Bustos Medina et al, 2013; Houben and Treskatis, 2007; Martin, 2013; Moorman et al, 2020; Moser et al, 2021; Sun and Xu, 1980; Zhang et al, 2021). However, clogging processes rarely occur alone, biological clogging is most often combined with physical or chemical clogging during MAR (Baveye et al, 1998; Beek, 2018; Burte et al, 2019; Camprovin et al, 2017; Cui et al, 2018; Fernández Escalante, 2015; Moser et al, 2021; Rinck‐Pfeiffer et al, 2000; Sarmin and Kazi Matin, 2014). Although there have been some studies of the mechanisms of combined clogging, such as physical–biological clogging (Cui et al, 2021; Wang et al, 2020) and bio–chemical clogging (Martin, 2013; Moser et al, 2021), the interactions between different clogging mechanisms are still largely unknown.…”