Due to work schedule and already high temps here in Phoenix, I am having the pool RO filtered instead of draining and filling. My current TDS level is a shocking 18,000 and salt level is 9000! I measured Calcium Hardness at 1625. I have been using only liquid chlorine for the last 3 years and actually it has worked quite well. We have pretty hard water and a high evaporation here which am sure is a big factor and I only backwash when pressure rises. Hopefully, I will be able to post good results tomorrow.