HM Digital TRM-1 Triple Inline TDS Monitor

Part #: 212436
Regular price List Price $144.78
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The HM Digital TRM-1 is a three sensor TDS monitor that allows you to check TDS at three different points. This is ideal for use in systems that utilize both reverse osmosis and deionization, or for checking multiple points in an RO system. This is a perfect accessory for aquarium enthusiasts, allowing you to quickly and easily determine when to change your RO membrane or DI cartridge.

  • Available with 1/4", 3/8" or 1/2" quick connect fittings
  • Highly efficient and accurate due to its advanced microprocessor technology
  • Displays TDS levels from 3 different points with electrode probes
  • Auto-off function -- Automatically shuts off meter after 10 minutes of non-use to conserve battery power
  • Dual range 0-9990 ppm (from 0 - 999 ppm the resolution is 1 ppm. From 1000 to 9990 ppm, the resolution is 10 ppm)
  • Factory calibrated -- HM Digital meters are calibrated with a 342 ppm NaCl solution. Meters can be recalibrated with a mini-screwdriver.
  • Installs quickly and easily
Use the following formula to calculate the percentage of solids (TDS) that your membrane is removing:


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