AquaHouse Large UV Pre-filter Sediment Replacement Cartridge AH-SED105BB-UV Suitable for removing rust and sediment particles from the water prior to a large UV lamp, to help ensure proper functioning of the lamp and to help protect the quartz sleeve from fogging 5 Micron rated sediment filter. Replace filter as required - dependent upon usage and water quality AquaHouse replacement sediment filter code: AH-SED105BB-UV?? for AquaHouse Large UV pre-filter system (model AH-UVPRE?-BB) AquaHouse branded filter, Aquahouse is a registered trademark of Water Filter Man Ltd