This kit tests for Total Dissolved Solids using the Direct Reading Titrator method. Range and sensitivity is 0-2000 ppm/20 ppm CaCO3.
The procedure involves 2 acid-base titrations. The first is a direct titration of the negative ions. The second is a titration of positive ions after all positive ions have been exchanged for hydrogen in an ion exchange column. The sum of the titration results equals ppm TDS as CaCO3.