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- Hanna Instruments GroLine Monitor for Hydroponic Nutrients HI981420
- 3 sensors combined in a single rugged probe body
- IP65 rated enclosure
- Wide pH Range
- Selectable EC to TDS/ppm conversion factor
- Automatic Temperature Compensation
- Large LCD with plant-friendly green backlighting
- Data logging for 30 days
- Data transfer
- High and low alarms
- Ambient light sensor
One quick glance is all it takes.
A large clear LCD displays all of your essential readings so you know what your hydroponic nutrients solution is doing 24/7. High and low alarms flash warning you if something needs adjusting.

Monitor changes over time.
The GroLine Monitor automatically logs your results every 15 minutes over the last 30 days. Minimum, maximum, and average values are stored so you can recognize when patterns arise and help prevent future problems.

One probe. Three measurements.
Our 3-in-1 pre-amplified probe measures pH, EC/TDS, and temperature in a single, durable, polypropylene body making the GroLine Monitor easy to handle and easy to set up.

Quick Cal for less maintenance.
A single calibration solution for pH and conductivity makes calibration fast and ensures all of your measurements are accurate all of the time for better plant health and better yield.

Professional level accuracy.
Advanced algorithms and greater pH and TDS/ppm accuracy ensure operational consistency and a finer understanding of your plant’s needs.
Measure like a pro.
Our GroLine Monitor is made by growers and scientists alike who are committed to helping you take your growing operation to the next level.
pH Specifications
| pH Range | 0.00 to 14.00 pH |
|---|---|
| pH Resolution | 0.01 pH, (0.1 pH) |
|
pH Accuracy (@25ºC/77ºF) |
±0.05 pH, (± 0.1 pH) |
| pH Calibration | one or two-point calibration (using pH 4.01,7.01, 10.01 buffers) using auto buffer recognition; one-point calibration using quick calibration solution |
|
Temperature Compensation |
automatic (0.0 to 60.0ºC/ 32.0 to 140.0°) |
Conductivity (EC/TDS) Specifications
| EC Range | 0.00 to 10.00 mS/cm |
|---|---|
| EC Resolution | 0.01 mS/cm |
| EC Accuracy | ±0.1mS/cm (0.00 to 5.00mS/cm); ±0.2mS/cm (5.00 to 10.00mS/cm) |
| EC Calibration | one-point at 1.41 mS/cm or 5.00 mS/cm using auto standard recognition; one-point calibration using quick calibration solution |
| EC/TDS Temp. Comp. | automatic with β set at 1.9%/°C |
| TDS Range | 0 to 5000 ppm (TDS conversion factor 0.5 (500 CF)); 0 to 7000 ppm (TDS conversion factor 0.7 (700 CF)) |
| TDS Resolution | 10 ppm |
| TDS Accuracy | ±2% f.s. |
Temperature Specifications
| 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 |
Specifications
| Display | 128 x 64 pixel B/W LCD with green backlight |
|---|---|
| Connectivity | USB Type-C |
| IP Rating | IP65 |
| Alarms | High and Low with enable/disable option for all parameters |
| Log Feature | Automatic logging for last 30 days at 15 minute interval |
| GLP | Good Laboratory Practice with last 5 pH and EC calibration history |
| Probe | HI1285-8 pH/EC/TDS/temperature polypropylene body, pre-amplified multiparameter probe with internal temperature sensor DIN connector and 2 m (6.6’) cable |
| Power Supply | 12VDC adapter (included) |
| Environment | -5 to 50°C (23 to 122°F); RH max 95% non-condensing |
| Dimensions | 125 x 185 x 38 mm (4.92 x 7.28 x 1.49”) |
| Weight | 333g ( 11.7oz.) |
| Includes | HI1285-8 multiparameter probe, HI50036-0 Quick Cal buffer solution sachet (2), HI700661P Electrode cleaning solution sachets for agriculture (2), 12VDC adapter, instruction manual, Monitor Quality Certificate, & Probe Quality Certificate. |
| Warranty | 2 years (probe 6 months) |