I'm not disagreeing with you...I'm just saying that adding quality prefilters to my RO Buddie extended the life of the DI resin significantly. My conclusion has always been that there was chlorine getting through the RO Buddie prefilters that was attacking the RO membrane and putting additional load on the DI resin. To that end, quality prefilters achieved my goal in extending resin useful life.As mentioned above, the prefilters prepare the water for the membrane so the membrane can do its work. The prefilters probably removed the larger solids that then allowed the membrane to do the remainder.
Again I was wrong in saying that they remove an abundant amount of TDS however, they remove some.