It is assumed that enlarged attached substances, which are frequently observed in biofilm treatment, grow while undecomposed substances in wastewater and microorganisms are attaching to each other on biofilm formed on the carrier at first. Then, enlarged attached substances are formed.

Several days after using GENKI, large lumps starts to fall off (exfoliate). Observation in the laboratory confirmed that attached substances fall off while leaving a thin biofilm as it is. A function that weakens cohesiveness between components (microorganisms and suspended solids) of attached substances is thought to be the cause. (MBR film contaminant control is thought to have a similar mechanism.)