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 Product! EC-3M Conductivity Tester
New Product! EC-3M Conductivity Tester

The EC-3M is a handheld meter that measures Electrical Conductivity with a range of 0-9.99 millisiemens (mS). It includes a built-in digital thermometer and an easy-to-read LCD screen as well as a convenient vinyl carrying case with belt clip.

Read More ...
Indoor Gardening Expo - Boston
Indoor Gardening Expo - Boston

The biggest trade show for hydroponics, indoor gardening and greenhouses will be in Boston, MA, October 18-19, 2014 at the John B. Hynes Convention Center. Visit us at booth #429.

Read More ...