The First Gate-Filters (100 microns with reverse washing) eliminates sand, aggregate, cement, dust...The second and third filters (carter 25 microns with active pure charcoal) for total absorption of chlorine and others who affect taste and odors.
The Fontin Ultrafiltration Membrane with microspores structure (pore diameter 0,01µ) Membrane area 1.2M² per module, flow outside-inside eliminates all Pathogenic micro-organisms (microbes) and viruses such Giardia, Cryptosporidium are, Salmonella (Thyfoid), Shigella, Polio, Hepatitis are completely eliminated.
Reverse Osmosis eliminates all microorganisms but all natural minerals too: A re-mineralization is needed (high cost from the basic unit cost, to maintenance or to added minerals stage)