I have an 8 year old water softener that is only softening to about 6 grains per gallon. This is an improvement over the city water's 20 grains, but is still not good enough because I need to protect my new tankless water heater. I had a local water softener assembler inspect my system and they said the resin has chlorine damage due to age and I need to replace the resin. He quoted me $600 for new 1 ft^3 of resin and a valve rebuild. The valve is a Fleck 5600. Resin by itself would be $450, which still seems high. Does anyone know where I can buy a high quality bag of resin for a little cheaper than this so I can do it myself? I should be able to get a rebuild kit straight from Fleck and do this myself too.