Hanna Instruments Worldwide
The Hanna Advantage: A Worldwide Leader in Technology and Innovation 100% Quality  360 Value
Contact Hanna: (65)6296-7118
Hanna Instruments Worldwide
Contact Hanna: (65)6296-7118

Professional Tools for Growers

From farms, greenhouses, and homes we provide innovative instrumentation for Professional growers. The GroLine product family includes products to measure pH, conductivity and
total dissolved solids (TDS). We offer meters from handhelds to nutrient dosing systems, and many include our unique CAL Check capability to identify the probe is working correctly.
Over time, traditional pH probes can develop micro fractures in the sensing glass or internal glass stem and read pH 7 regardless of the actual value. This problem is compounded by a
single point calibration to pH 7 when the expected readings are close to pH 7. GroLine is complete with a line of maintenance solutions including specialized cleaning, storage,
and calibration standards.

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GroLine testers are convenient and inexpensive ways to measure pH, conductivity (EC) or Total Dissolved Solids (TDS). Our selection of handheld meters includes basic pH and EC/TDS meters that can be used with nutrient solutions and soil slurries. We also offer testers for the direct measurement of pH and for EC/TDS with specialized probes that can be used with soils, rockwool, and other growing mediums without the need to make a slurry.

Portable Meters

We offer many portable meters for pH, conductivity (EC) and Total Dissolved Solids (TDS). The GroLine product offering includes a multiparameter portable designed specifically
for the grower. Features of value include being waterproof, adjustable EC to TDS factor, and Hanna’s CAL Check feature to ensure that measurements are not taken with a faulty probe. Meters can use a variety of probes including one that allows for the direct pH measurement of soli and other media without having to make a soil slurry.

Nutrient Monitoring and Control

The monitoring and control of nutrient solutions is critical to successful propagation and optimization of plant growth. Different plant species have an optimal pH for nutrient
uptake and growth. For those that have source water with a high alkalinity resulting in an elevated pH will add acid to adjust the pH to the right level. This process can be automated
with a dosing pump to maintain the ideal pH for the plant. Just as with pH every plant has an optimal fertilizer concentration for maximizing plant growth. It is essential to monitor the concentration whether by conductivity (EC) or Total Dissolve Solids (TDS). As freshwater is added to a reservoir tank the fertilizer will decrease in concentration and should be corrected. This process can be done manually by hand or automated with a dosing pump to maintain the ideal EC/TDS for the plant.

Calibration Solutions

GroLine calibration solution is available in a variety of sizes based on the frequency of use, infrequent use includes users that calibrate and measure on a weekly or monthly
basis rather than users who calibrate throughout the day.  It is important that open solution be used within six months of opening a bottle and should be changed after six
months for optimum performance.  All solutions are supplied with a COA and include Quick CAL solution that is used for both pH and EC/TDS calibration. This dual-purpose
calibration solution is used with compatible meters with the Quick Cal mode or with pH and conductivity meters that calibrate to pH 6.86 and 5.00 mS/cm.

Maintenance Solutions

All glass pH electrodes need to be stored properly to guarantee an accurate calibration and to protect the pH electrode from premature failure. A few drops of storage solution will maintain the hydrated layer on the glass bulb and prevent the reference junction and electrolyte from drying out.

It is also important to maintain a clean pH sensor. Any coating to the sensitive glass bulb or clogging of the junction will impede the electrical circuit, resulting in erratic
and misleading readings. GroLine cleaning solution is formulated to remove soil and humus deposits to ensure the maximum performance from the pH electrode
and provide readings you can depend on.