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Handheld TDS Meters
Inline TDS Meters
TDS Meter Parts, Calibration Fluid and Accessories
Simply enter your Feed Water TDS and RO Water TDS into the boxes above and click "Submit". The percentage of TDS Rejection will be displayed. We normally recommend membrane replacement once you drop below 75%. This may vary in areas with high TDS in the feed water.
See our selection of TDS meters under Water Tests