Hanna Instruments TDS-1 Dissolved Solids Tester- This precision, digital instrument accurately measures the parts per million of your product if only silver and pure distilled water are present. The purchase of a tester is not absolutely necessary since our instructions and timing techniques can give a fairly accurate estimation of strength, but it is a good investment to insure the exact potency of the product being produced and the quality of the distilled water you start with.

TDS Tester Replacement Batteries
TDS Tester Calibration Solution