i cant see how 2 resin vessel can save me on resin, does anyone have real proof of this, the real idea of 2 di resin vessels, came about years ago, it was for folk with high tds readings, who mainly do commercial work, and this method was to fill up on site, saving them running back to refill, if they had a tds of say 400 or more, one vessel was not enough to bring that hardness down, so the 2 vessels where born, i think over the years the whole thing has been misinterpreted, 2 vessel will still give the same results as one vessel, i think it will still come to the same calculations when the resin is spent, prove me wrong, becouse i just dont believe it