Loading... Please wait...

HM-500 HydroMaster: EC/TDS, pH, Temperature Monitor

$360.00 $239.99 (You save $120.01)
Calculated at checkout

Product Description

The versitile HM-500 continuous monitor indicates EC/TDS, pH, and Temperature. With its rechargeable, integrated battery this unit is portable, or can be wall mounted with the included bracket, or can be used bench-top with the integrated stand. To make it even more user-friendly, the HM-500 comes equipped with touch screen, high and low alarm set points, and recorded readings. It is ideal for hydroponics and other applications such as labs, pools, and aquariums.


Continuous pH/EC/TDS/Temperature Monitor
Rechargeable battery
RF Resistant
Portable, wall mount, or benchtop use
Data Storage: Up to 20 measurement readings
Auto Shut-Off: After 5 minutes
Alarm: Adjustable High & Low Set Point and on/off
Display: LCD Touch-Type Screen with auto back lighting
Probe: ABS with platinum electrodes for EC / single junction pH sensor
Warranty:  3 years


Measurement Scales
  pH: pH
  Temperature: °C, °F
  TDS: ppm (0.5 / ppm (0.7) / ppt (0.5) / ppt (0.7)
  EC: µS / mS
  pH: 0.00 – 14.00 pH
  Temperature: 0.0 – 80.0 °C / 32.0 – 176 °F
  TDS: 0 – 9999 ppm / 0 – 10.00 ppt
  EC: 0 – 9999 µS / 0 – 20.00
  pH: 0.1 pH
  Temperature: 0.1°C / 0.1 °F
  TDS: ppm: 0.1 ppm (0 – 99.9 ppm) / 1 ppm (100 – 9999 ppm) / ppt: 0.01 ppt (0 – 10.00 ppt) EC: µS: 0.1 µS (0 – 99.9 µS) / 1 µS (100 – 9999 µS) / mS: 0.01 mS (0 – 20.00 mS)
ATC: Yes
  pH: ± 0.02 pH
  Temperature: ± 0.5v
  TDS: ± 0.2%
  EC: ± 0.2 %
Power Source: AC 110 V – 220V / Rechargeable integrated Lithium Ion Battery
Suitable Ambient Conditions: 0 – 50°C (0-122°F) / RH 80% (EC Probe: 0 – 80°C)

Write a review

Product Reviews

  1. Great piece of kit with little coverage. 5 Star Review

    Posted by on 8th Feb 2021

    Shocking how cool this combo monitor is yet there are so few reviews for it. I was nervous about it at first but it's been amazing so far and worth every penny.

  2. Hidden secret to the best aquarium 5 Star Review

    Posted by on 25th Oct 2017

    Don't even want to review this product because it's been my little secret to keeping my planted freshwater aquarium in top shape. I freaking love the quality of this thing.

Welcome to Buckeye Hydro!
Pure Water Technologies

Our Newsletter

Sign up for exclusive updates and special offers!


Buckeye typcially ships the same day, or less commonly, the day after an order is placed. The majority of our shipments are sent UPS Ground or FedEx Ground. Estimated delivery times for these services are similar, and are shown below. See our policies page for additional shipping information.

Read More About Shipping


When should I replace my filters?
Will Buckeye filters fit properly in my water filtration system?
Do I need to do anything special when I install new cartridges in my RO or RO/DI system?

Read More FAQ