... :4",6",8",10" Casing:UPVC,SS,FRP water filter system--Ultra filtration membrane water filtering filter for water treatment with different membrane material (PES,PS,PVDF,PVC ... Flushing Cycle6-180daysChemicals Flushing Time15-120minsChemicalsCitric acid,NaOH / NaClO,H2O2 UF water treatment filter for water filter system