How long did your cell last?

[PJM361]

Very little scale, the reason I called Hayward was because the check cell light kept coming on and my salt level reading was 2000ppm when I opened the pool this year. After adding a bag of salt the # went down to 1900 then hours later went slowly up to 2700 , but still would only run with limited output (low salt flashing) then added another bag and the # actually went down to 1700. I was having problems at the end of last season with fluctuating numbers. So I did the acid wash. What is CSI?