HM Digital DM-1: In-Line Dual TDS Monitor

HM Digital DM-1 is a consumer-friendly TDS monitor that measures the input and output of a water filtration system. It measures the feed water (input) versus the product water (output) at any time. It became ideal for everse Osmosis (RO), Deionized water (DI) filtration systems that works perfectly in applications like Aquariums, Hydroponics, drinking or potable water and many more.

Price incl. GST

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Categories: , SKU: DM-1


  • Factory Calibrated:Meters are calibrated with a 342-ppm NaCI solution that can be re-calibrated with a mini-screwdriver.
  • With an advanced microprocessor technology that is efficient and accurate
  • Displays TDS levels feed water and product water with in & out electrode probes
  • Quick and easy installation
  • Comes equipped with two 1/4-inch T-fittings (also available in 3/8″ and 1/2″)
  • Has auto-off function that helps conserve battery power. (Shuts off automatically after 10 minutes of non-use)

Additional information

Weight 0.085 kg


Size: 7.6 x 2 x 4.7 cm (3 x .8 x 1.9 in.)

Accuracy: ±2%

Range:  0-9990 ppm Dual Range 0-9990 ppm (From 0 – 999 ppm the resolution is 1 ppm. From 1000 to 9990 ppm, the resolution is 10 ppm, indicated by a blinking ‘x10’ image.)

Conversion Factor: NaCl (avg. 0.5)

UPC: 891144000052

Weight: 79.4 g (2.8 oz.)

Battery Life: approximately 1000 hours of continuous use

Fittings: 1/4″ standard, also available with 3/8″ or 1/2″

Power Source: 2 x 1.5V button cell batteries (LR44 or equivalent; included)

Cable Length: 24.5″ (including sensor)


  • Hydroponics
  • Drinking Water
  • Food & Beverage
  • Aquarium
  • Water Treatment
  • Aquaculture
  • Window Cleaning/Carwash