I live in the desert and the water here is horrible. The water is about 500-600 TDS (total dissolved solids) which from what I understand is very high. I purchased a DIC-20 CR Spotless system and it works very well, but the resin doesn't last long at all. I contacted the company and with the TDS I have, they say I will only get approximately 10 washes at best with it before having to replace the resin. I added another inline cartridge filter and seem to get about 12-15 washes now before having to replace the resin. Anyone found a good way to extend the resin? Or found a better way to get spot free washes with bad water?