JavaScript seems to be disabled in your browser. For the best experience on our site, be sure to turn on Javascript in your browser.
Low Prices and Fast Shipping
Since 1999
TDS Meters For Testing of Total Dissolved Solids in the Water From Your 3M, Aqua-Pure, CUNO or Water Factory Reverse Osmosis System. Chose handheld or inline TDS meters. Low prices and fast shipping since 1999.
Handheld PH Meters For Accurate Water Testing - Check for alkalinity and acidity. Alkaline and acid water testing levels. Test your water now. Low prices and fast shipping online since 1999.
Water Testing, TDS Meters and Test Supplies. Large selection, low prices and fast shipping since 1999.
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