are potassium chloride and regular softner salt interchangeable for use in a water softner?
Yes it's true, all water softeners can use either or both sodium chloride or potassium chloride. Go to any resin manufacturers' web site and see or ask. So those folks that are saying their softener only uses potassium are uninformed or lying. In some cases with the use of potassium and high iron content water, you may have to use a slightly higher salt dose.