HI98129 pH/Conductivity/TDS Tester (low range)

The HI98129 makes measuring pH quick and easy! This lightweight, waterproof tester offers high accuracy pH, EC/TDS and temperature measurements in a single handheld unit! No more switching between meters for your routine measurements.


The HI98129 is a highly accurate, waterproof pH meter that can also measure EC/TDS and temperature. This floating, waterproof combination tester has an easy to read, LCD and an automatic shut-off. In addition, pH and EC/TDS readings are automatically temperature-compensated to prevent temperature related variations in your measurements.

The EC/TDS conversion factor is user selectable as well as the temperature compensation coefficient.

Replaceable pH Electrode Cartridge

The HI98129 tester features an easy to replace pH electrode cartridge with an extendable cloth junction. The extendable cloth junction helps increase electrode life and the replaceable pH cartridge means that this tester does not need to be thrown away when the pH sensor is exhausted. Also, the sturdy, snap-in connector means there are no pins to bend or break!


  • Features at-a-glance

    Waterproof and designed to float Automatic Temperature Compensation HOLD button to freeze readings on the display BEPS Alerts the user of low battery power that could adversely affect readings


pH Range 0.00 to 14.00 pH
pH Resolution 0.01 pH
pH Accuracy ±0.05 pH
Conductivity Range 0 to 3999 µS/cm
Conductivity Resolution 1 µS/cm
Conductivity Resolution 1 µS/cm
Conductivity Accuracy ±2% F.S.
TDS Range 0 to 2000 ppm (mg/L)
TDS Resolution 1 ppm (mg/L)
TDS Accuracy ±2% F.S.
Temperature Range 0.0 to 60.0°C / 32.0 to 140.0°F
Temperature Resolution 0.1°C / 0.1°F
Temperature Accuracy ±0.5°C /±1°F
EC/TDS Calibration automatic, one-point at: 1413 µS/cm, 1382 ppm (mg/L)
pH Calibration automatic, at one or two points with two sets of standard buffers (pH 4.01 / 7.01 / 10.01 or pH 4.01 / 6.86 / 9.18)
Temperature Compensation pH: automatic; EC/TDS: automatic with β adjustable from 0.0 to 2.4% / °C
TDS Conversion Factor 0.45 to 1.00
pH Electrode HI73127 (replaceable; included)
Battery Type/Life 1.5V (4) / approx. 100 hours of continuous use, auto-off after 8 minutes of non-use
Environment 0 to 50°C (32 to 122°F); RH max 100%
Dimensions 163 x 40 x 26 mm (6.4 x 1.6 x 1.0'')
Weight 100 g (3.5 oz.)
Ordering HI98129 (Combo) is supplied with HI73127 pH electrode and HI73128
Information electrode removal tool, batteries and instructions.