Systems designed to filter mains water are not appropriate to use for rainwater. Unlike mains water, rainwater is not chlorinated. Consequently, you need to take into account the presence of bacteria when installing a filtration system for rainwater.
Filterite offers 2 systems to filter your rainwater.
The Filterite Twin Ultraviolet Steriliser System incorporates a twin undersink water purifier with ultraviolet sterilisation and includes: