TDS

Definition

TDS (Total Dissolved Solids) is the sum of all dissolved minerals + ions in water, measured in ppm via electrical conductivity.

Practical use

Tap water TDS: 50-500+ ppm (highly variable). RODI output target: 0 ppm. Replace DI resin when TDS climbs above 1 ppm at the output. Test with a handheld TDS meter.

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