The salt level reading on the Prologic display is higher than what I am getting on the test strips. In one day I had a reading of 3700 at the start and 3500 by the end of the day. I have taken out the cell and cleaned it, readings still off. I have also noticed that without adding salt to the pool the reading will also increase. Any ideas if it just needs to be reset (not sure how I do that) or I need a new cell?