How do the Pocket Pro and Pocket Pro+ TDS (total dissolved solids) testers determine TDS?
Pocket Pro TDS determination
TDS results are derived from conductivity. The Pocket Pro and Pocket Pro+ TDS testers use a TDS factor of 0.71 by default. This factor can be adjusted and for best accuracy it should be determined by a USEPA gravimetric method such as Hach method 8163. Gravimetric methods determine true solids content by a combination of filtering, evaporation and weight.