Okay so read the instructions over again. The reading on the old filter was 01 which is 100 @ppt and must be multiplied by 1000 to get the ppm. So that would be 100,000 but that a decimal point will be between the 2nd and 3rd digits. So that would be a reading of 10ppm.... Is this correct? Very confusing.....

Eitherway I replaced the filters and got a reading of 00.....