I have a 18000 gal vinyl inground pool with a Mineral Springs System and a Hayward DE 4800 Filter. At the end of last year the MS unit was not producing chlorine due to low salt readings. I had the water tested a number of times and each time the salt levels were within range. I am trying to determine if purchasing a new cell will solve the problem or if I need to explore other options. Does anyone have any suggestions?