For those of you who use di only.. How fast do you fill your tanks? Do you turn the tap on full? I was filling my 350 tank in approx 30mins.. My tap water is only 042 ish... Last Monday I checked my ppm in tank and it was 010... So thought I'd better order some resin... I got my mothers wooden spoon and gave the resin a good stir.. The ppm dropped to 006. So I used my tank on Monday.. Rained all day Tuesday.. On Tuesday night, I filled my tank as slow as possible... The ppm was 003... I got approx another 1500lts and ppm now only 008... So my conclusion is... Does resin last longer the slower the water passes through the di vessel? - I used to purify on the go.. With the di in the van.. So the water would be passing through the di roughly @ 2.5lt a min.. From I removed the di from the van and started filling tank with pure ( so I can fill trolley quickly ) I thought I was using more resin than when di was in the van.... Where I am filling at home the water is going over 10lt per min.... Could we be throwing away good resin?