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Hanna Instruments GroLine Nutrient Monitor with Probe



SKU: TST-HI-981421

Monitor your hydroponic nutrient solution like a pro with the HI981421 GroLine Monitor. The inline probe comes with a 3-in-1 sensor that’s pre-amplified and measures pH, EC, and temperatures all in one. Built-in at the end of the probe is a 3/4″ threaded connection compatible with hydroponic tubing for in-flow monitoring. Data is logged every 15 minutes and saves results over a 30-day period for long-term monitoring which can be viewed on the mountable monitor, the large LCD screen also showcases the most essential readings in just a quick glance.

  • 24/7 pH/EC/temperatures readings
  • Easy calibration with Quick Cal
  • USB Type-C connectivity

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Hanna Instruments GroLine Nutrient Monitor with Probe

The HI981421 GroLine Monitor for Hydroponic Nutrients provides around-the-clock, continuous monitoring of pH, conductivity (EC & TDS), and temperature in hydroponic nutrient solutions. Quick to set up and simple to use, this monitor was designed with Hydroponics, Aquaponics, and Greenhouses in mind. Make your nutrient solution easy to manage with the GroLine Monitor.

Features at-a-glance

  • 3 sensors combined in a single rugged probe body made for continuous immersion up to 2 meters:
    • pH electrode with renewable cloth junction
    • Amperometric EC/TDS sensor
    • Internal temperature sensor
  • IP65-rated enclosure: designed to withstand harsh grow environments
  • Wide pH Range: measure pH from 0.00 to 14.00 pH
  • Selectable EC to TDS/ppm conversion factor: choice of either a 0.5 or 0.7 conversion factor
  • Automatic Temperature Compensation: all readings are compensated for variations in temperature, temperature displayed in oC or oF along with pH, EC, or TDS reading
  • Large LCD with plant-friendly green backlighting: LCD can display all three essential hydroponic nutrient measurements at one time, a 3-second cycle of single measurements, or a real-time graph screen with options for measurement selection and log recall
  • Data logging for 30 days: logs every 15 minutes for last 30 days, stores min, max, and average values
  • Data transfer: USB-C port for easy data transfer to a memory stick or PC
  • High and low alarms: warns when your nutrient solution is out of desired range by flashing display and message
  • Ambient light sensor: for automatic LCD dimming

HI981421 GroLine Nutrient Monitor Instruction Manual

Weight .73 lbs
Dimensions 14.5 × 7.5 × 2 in


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