In-Line Monitors




We offer a wide selection of water quality testers that will accurately measure the TDS level in your tap (feed) water and purified (product) water, as well as measuring waterflow and volume. These monitors enable you to determine how good (or bad!) your water really is.

Products


HM Digital FLM-3 Flow MonitorHM Digital FLM-3 Flow Monitor
Part Number: FLM-3
HM Digital FLM-3 Flow Monitor The HM Digital FLM-3 Flow Monitor checks and measures the flow rate of a water line. The innovative FLM-3 will alert when the flow rate exceeds a specific user-set limit. The battery-powered FLM-3 features an LCD...
  • Warranty: 1 year
  • Resolution: 1 (0-999) ppm
  • Power Supply: 2 x 1.5V AA batteries
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$36.99 

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HM Digital LDM-100R Commercial Grade Dual Line EC/TDS MonitorHM Digital LDM-100R Commercial Grade Dual Line EC/TDS Monitor
Part Number: LDM-100R

  • Warranty: 1 Year Manufacturer Warranty
  • TDS Range: 0-9999 ppm / 0-10.0 ppt ppm
  • Power Supply: 2 x 1.5V AA batteries
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$92.29 

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HM Digital LSM-100 Commercial Inline EC/TDS MonitorHM Digital LSM-100 Commercial Inline EC/TDS Monitor
Part Number: LSM-100
Alternate Part Number: LSM-100R
HM Digital LSM-100 Commercial Inline EC/TDS Monitor The HM Digital LSM-100 is the ideal EC/TDS monitor for commercial or industrial applications. Ideal for Large Scale Systems. The extended battery life as well as 1/2" sensor probe makes the...
  • Warranty: 1 year
  • TDS Range: 0-9999ppm / 0-10.0 ppt ppm
  • Resolution: 0-99.9: 0.1 ppm/µS; 100-9999: 1 ppm/µS ppm
  • Power Supply: 2 x 1.5V AA batteries
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$64.03 

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HM Digital PM-2-NF External Inline TDS Purity Monitor with TransformerHM Digital PM-2-NF External Inline TDS Purity Monitor with Transformer
Part Number: PM-2-NF
  • Available with 1/4", 3/8" or 1/2" quick connect fittings
  • External single line internal TDS monitor that is ideal for most water purification systems.
  • Includes a light and optional alarm that alerts the user service is required when the TDS level reaches the pre-programmed set-point.
  • Set points of any even number between 2 and 200 ppm
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    $56.00 

    5+ for $50.40 ea
    10+ for $46.20 ea
    20+ for $43.40 ea

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    HM Digital PPH-1000 Industrial pH Controller with 3/8" Sensor ProbeHM Digital PPH-1000 Industrial Online PH Controller with 3/8
    Part Number: PPH-1000
    HM Digital PPH-1000 Industrial pH Controller with 3/8" Sensor Probe The HM Digital pH Controller is an industrial online monitor and controller of pH levels. The PPH-1000 is used in a variety of water solution treatment applications such as...
    • Temperature Range: 0-80°C / 32-176°F
    • Resolution: 0.01 pH / 0.1 °C (°F) ppm
    • Power Supply: AC 110 V / 220 V
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    $321.43 

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    HM Digital PSC-60D Dual Inline EC/TDS MonitorHM Digital
    Part Number: PSC-60D
    HM Digital PSC-60D Dual Inline EC/TDS Monitor The HM Digital PSC-60D Dual Inline EC/TDS Monitor reads in an extended range to monitor and control electrical conductivity (EC) and total dissolved solids (TDS) levels for high output systems...
    • Warranty: 1 year
    • TDS Range: 0-9999 ppm
    • Temperature Range: (0-75°C) / (33-167°F)
    • Resolution: TDS 0.1 ppm (0-99.99)/1 ppm (100-9999) ; EC 0.1 µS (0-99.99)/1 µS (100-9999) ppm
    • Power Supply: AC 110 V - 220 V
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    $109.86 

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    HM Digital PSC-64D Mini Dual Display EC/TDS Monitor with 4-20mA OutputHM Digital PSC-64D Mini Dual Display EC/TDS Controller with 4-20mA Output
    Part Number: PSC-64D
    • Warranty: 1 Year Manufacturer Warranty
    • TDS Range: 0 - 9999 ppm /0 - 10 ppt ppm
    • Temperature Range: 33 - 167 °F
    • Resolution: See Spec Sheet ppm
    • Power Supply: AC 110V - 220V
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    $135.99 

    10+ for $126.47 ea
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    HM Digital DM-2 Commercial In-Line Dual TDS MeterHM Digital DM-2 Commercial In-Line Dual TDS Meter
    Part Number: DM-2
    • Available with 1/4", 3/8" or 1/2" quick connect fittings
    • Installs quickly and easily
    • Diagnostic error messaging
    • Shielded sensor cables
    • Highly efficient and accurate due to its advanced microprocessor technology
    • Auto-off function automatically shuts off meter after 3 minutes of non-use to conserve battery power
    • Displays TDS levels of the feed water and product water with in and out electrode probes
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      MSRP: $58.00
      $44.63 - $51.51

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      5+ for $45.88 ea
      Set of 10 for $42.46 ea
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      HM Digital DM-1 Dual TDS MeterHM Digital DM-1 Dual TDS Meter
      Part Number: DM-1-2538
      • Available with 1/4" and/or 3/8" quick connect fittings
      • Highly efficient and accurate due to its advanced microprocessor technology
      • Displays TDS levels of the feed water and product water with in and out electrode probes
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        $27.99 - $35.09

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        5+ for $27.71 ea
        Set of 10 for $25.65 ea
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        HM Digital TRM-1 Triple Inline TDS MonitorHM Digital TRM-1 Triple Inline TDS Monitor
        Part Number: TRM-1-38
        • Available with 1/4", 3/8" or 1/2" quick connect fittings
        • Displays TDS levels from 3 different points with electrode probes
        • Highly efficient and accurate due to its advanced microprocessor technology
        • Dual range 0-9990 ppm (from 0 - 999 ppm the resolution is 1 ppm. From 1000 to 9990 ppm, the resolution is 10 ppm)
        • Installs quickly and easily
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          $40.00 - $42.00

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          5+ for $39.48 ea
          Set of 10 for $36.54 ea
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          HM Digital FM-1 Filter Monitor With Water Flow SwitchHM Digital FM-1 Filter Monitor With Water Flow Switch
          Part Number: HMFM-1
          Alternate Part Number: FM-1
          • Includes a carrying case with belt clip.
          • Highly efficient and accurate
          • Hold Function
          • Built-in digital thermometer
          • Display: large and easy-to-read LCD screen.
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            MSRP: $45.00
            $29.65 

            5+ for $27.87 ea
            Set of 10 for $25.80 ea
            20+ Call

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            HM Digital FM-1 Filter Monitor - Meter OnlyHM Digital FM-1 Filter Monitor - Meter Only
            Part Number: HMFM-1A
            • Highly efficient and accurate
            • Hold Function
            • Built-in digital thermometer
            • Display: large and easy-to-read LCD screen.
            • FMS-1: water flow switch and FMD-1: LED faucet indicator disc NOT included
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              MSRP: $34.00
              $24.95 

              5+ for $23.45 ea
              Set of 10 for $21.71 ea
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              HM Digital PM-2 External Inline TDS Purity MonitorHM Digital PM-2 External Inline TDS Purity Monitor
              Part Number: PM-2-25
              • Available with 1/4", 3/8" or 1/2" quick connect fittings
              • External single line internal TDS monitor that is ideal for most water purification systems.
              • Includes a light and optional alarm that alerts the user service is required when the TDS level reaches the pre-programmed set-point.
              • Set points of any even number between 2 and 200 ppm
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              $59.28 - $78.56

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              5+ for $70.70 ea
              10+ for $64.81 ea
              20+ for $60.88 ea


              HM Digital QC-1 Quick Check TDS Monitor 1/4" Push-inHM Digital QC-1 Quick Check TDS Monitor 1/4
              Part Number: QC-1
              • Tests for TDS or conductivity levels.
              • Eight programmable set points (by dip switch).
              • Bright LED lights
              • Excellent reverse osmosis or deionization monitor
              • Available with 1/4" quick connect tee or with no fitting
              • Installs quickly and easily
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                MSRP: $28.95
                $18.80 - $22.85

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                5+ for $21.48 ea
                Set of 10 for $19.88 ea
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                HM Digital SM-1 Inline Single TDS Monitor 1/4" Push-inHM Digital SM-1 Inline Single TDS Monitor 1/4
                Part Number: SM-1
                • Displays TDS levels of a single water line.
                • Wide range 0-9990 ppm
                • Factory calibrated - Meters can be recalibrated with a mini-screwdriver.
                • Comes equipped with quick connect tee fitting (1/4" standard)
                • Installs quickly and easily
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                  MSRP: $35.00
                  $25.89 

                  5+ for $24.34 ea
                  Set of 10 for $22.52 ea
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