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Hanna GroLine Combo pH/EC Meter



SKU: TST-HI-98131

The HI98131 is a slim, lightweight, and waterproof pocket-sized meter that measures pH, conductivity (EC), total dissolved solids (TDS) and temperature. The meter operation is simplified with two buttons. One is used for on/off and for calibration while the other is used to switch between the measurement modes. The HI98131 has advanced features including a selectable EC to TDS conversion factor (0.5 – 500 ppm and 0.7 – 700 ppm).

  • Quickly and accurately measure temperature, pH, and TDS/EC in your nutrient solution.
  • Quick Cal solutions to calibrate pH and conductivity all at once with a single solution.
  • Waterproof design and 1-year manufacturer’s warranty ensure long device life.

In stock

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Hanna GroLine HI98131 Combo Meter

The HI98131 GroLine tester features a large multi-level LCD which displays both pH, EC or TDS and temperature readings simultaneously. The pH readings are displayed with a 0.01 resolution and with an accuracy of +/-0.05 pH, while the EC and TDS readings are displayed with a 0.01 mS/cm and 10 ppm (mg/L) resolution and 2% full-scale accuracy. The EC range of the HI98131 is from 0.01 to 6.00 mS/cm and TDS is from 0 to 3000 ppm using a 0.5 conversion factor. The HI98131 also offers the option to use a 0.7 (700 ppm) EC to TDS conversion factor. An exposed temperature sensor allows for rapid temperature compensated measurements of EC and TDS. The LCD screen has indicators for calibration status and stability. The battery percent level is displayed at startup alerting the user to the remaining battery power that is available. The HI98131 is a versatile pocket meter designed for hydroponics, greenhouse and agriculture applications.

Simplified one button calibration
One or two point pH calibration is automatic to a pre-programmed buffer set (4.01, 7.01 and 10.01) or single point pH and EC calibration with the Hanna Quick Cal calibration solution. To perform a quick cal calibration, simply press and hold the left power/mode button while in measurement mode for three seconds and let go to enter calibration mode. Once both pH and EC are calibrated “CAL OK” is displayed and the meter returns to measurement mode.

HI73127 Replaceable pH electrode
The HI99131 is supplied with the HI73127 replaceable pH electrode. This electrode features an extractable junction that can be pulled 1/8″ out to clear any clogging that results in drifting and erratic readings.

Features at-a-glance
• 3 sensors in a single meter
pH electrode with extractable junction
Amperometric EC/TDS sensor
Exposed temperature probe for faster EC/TDS readings

• Waterproof
Designed to withstand the humidity of a growing environment

• Wide pH Range
pH range is from 0.00 to 14.00 pH

• Selectable EC to TDS conversion factor
Choice of either a 0.5 or 0.7 conversion factor
0.5 (500 CF) conversion factor is for an EC reading of 1000 μS/cm = 500 ppm
0.7 (700 CF) conversion factor is for an EC reading of 1000 μS/cm = 700 ppm

• Automatic Temperature Compensation
All readings are compensated for variations in temperature
Temperature displayed in C or F along with pH, EC or TDS reading

• Stability indicator
The meter displays a clock tag that will disappear when the reading has achieved stability

• HOLD button
Freezes reading on the display to allow recording of measurement

• BEPS (Battery Error Prevention System
Meter will automatically shut off if there is not enough power to get an accurate measurement

• Battery % level at startup
• Low Battery Indicator
When the level is below 5%, the battery symbol on the LCD blinks to indicate a low battery condition.

• Auto-off
An adjustable timer will trigger the meter automatically shut off to conserve battery life. Options are after 8 minutes, 60 minutes, or disabled.

 Waterproof design and 1-year manufacturer’s warranty ensure long device life.

Weight 0.8 lbs

Probe Type




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