Thanks for the replies. My acid injector is the intelliph and I set how much acid it is to inject every 60 minutes. It, as well as the SWCG, is on a timer that runs 12 hours per day in conjunction with the pool pump and it currently injects 1.5 oz every 60 minutes. My SWCG is a Pentair IC40 and it is set at 5% on the intelliph control panel. My pool has never really demanded a lot of chlorine. As for my current salt levels, they have progressed up from 3500ppm in early 2012 to 4400ppm today. I have added zero salt since the pool was filled and the builder put the salt in (30 days after filling). That is what has me searching right now is how can my salt level be climbing without adding salt - my guess was sodium bicarbonate but I dont know. Thanks for the suggestion of the boric acid.