WATER TESTING INSTRUMENTS

Our handheld and portable TDS, EC, pH and ORP testers, in-line monitors, controllers and accessories for reverse osmosis (RO) water filters, water purification systems, hydroponics, aquariums, pools and many other applications are superior in construction and performance, yet made available at a very economic cost. HM Digital, Inc. is the only manufacturer of economical in-line dual TDS monitors that measure total dissolved solids (TDS) levels of feed and product water lines simultaneously, an effective way to compare rejection rates and gauge reverse osmosis membrane, water filter and water purification performance.

With HM Digital water testing instruments, you'll know if your water is pure.

Please click products to learn more about which TDS tester is right for you.

What is a TDS meter and what is TDS (Total Dissolved Solids)?

Product Highlight | Upcoming Events

New COM-80 EC/TDS HydroTester!
New COM-80 EC/TDS HydroTester!

HM Digital is proud to release it's brand new EC/TDS HydroTester (model COM-80). This economically priced handheld EC/TDS meter is perfect for hydroponics & gardening, pools & spas, aquariums & reef tanks and much more!

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Maximum Yield Indoor Gardening Expo - San Francisco
Maximum Yield Indoor Gardening Expo - San Francisco

The biggest trade show for hydroponics, indoor gardening and greenhouses. San Francisco, CA, July 27-28, 2013. Visit us at booth #420

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