I did a similar test for my Dad.
Here is the procedure used:
- 1L (Quart) of heated distilled water
- Take PPM measurment since heating increases conductivity
- 8 inch
rods in holder (comes with the full unit not lite)
- Set timer for one hour
- Stir with rod and holder assembly already in water
- Set timer for another hour
- Result was ~21PPM
Need to remove some of the initial PPM since the heated water had cooled some in the two hours but regardless the result was 16-18PPM, tasted great and was completely clear.