TDS Meter,Water Quality Tester Filter Pen, for for Drinking Water Purity Test

A high level of TDS is an indicator of potential concerns and should be investigated before drinking. The U.S. EPA suggests a maximum level of 500 ppm. Test the purity of drinking water to ensure it's healthy, monitor if Reverse Osmosis (RO)/DI System works properly, whether filter need replaced, maintenance aquarium, hydroponics(test nutrients) and pool etc.

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