Hanna GroLine - Products for the Hydroponics Grower

Hanna Instruments GroLine products are designed with the hydroponics grower in mind. All of our products are manufactured in house. Manufacturing includes the complete meter from the population of components on the circuit board to injection molding of the case used to house it. We form the glass pH bulb, which is then used to make a pH electrode. Very few companies have the actual expertise to do this. We also produce and package all the necessary solutions required to use our meters. Being a vertical manufacturer not only allows us to control the quality of the finished product but also the cost since there are no intermediaries to deal with. Below is a selection of meters, calibration solutions and maintenance solutions that are necessary tools to properly manage and monitor the pH and Conductivity/Total Dissolved Solids (ppm) of the nutrient solutions used to grow crops.



Waterproof Portable pH/EC/TDS Meter

Application Driven Performance

Hydroponic growers are faced with many difficulties when performing analytical measurements. Humidity, electrical noise from ballast and pumps, and pH calibration to a single point that is also close to the expected value, all can be challenging in obtaining an accurate reading. The GroLine portable pH/EC/TDS meter uses a single probe designed with an amplifier in the pH electrode that helps eliminate electrical noise resulting in a fast and accurate pH measurement. The pH electrode also has a buffered salt solution in the tip of the pH electrode that is at a different value from a standard pH electrode. Using a different pH buffered solution will result in a dramatically different measurement value from pH 7 being displayed in the event there is a hairline crack in the electrode.


Quick Cal Mode

Quick Cal mode allows the user to perform a single point pH and EC/TDS calibration with one solution. Simply enter calibration mode and the meter will prompt to confirm calibration to pH 6.86 and 5.00 mS/cm.


Multiparameter Measuring Modes

GroLine portable meters offer both Conductivity (EC) and Total Dissolved Solids (TDS) measuring modes. The EC measuring mode has an expanded scale to measure up to 6.00 mS/cm while TDS measuring range is up to 3999 ppm using a 0.7 conversion factor.


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Application Driven Performance

Hydroponic growers are faced with many difficulties when performing analytical measurements. Humidity, electrical noise from ballast and pumps, and pH calibration to a single point that is also close to the expected value, all can be challenging in obtaining an accurate reading. The GroLine portable pH/EC/TDS meter uses a single probe designed with an amplifier in the pH electrode that helps eliminate electrical noise resulting in a fast and accurate pH measurement. The pH electrode also has a buffered salt solution in the tip of the pH electrode that is at a different value from a standard pH electrode. Using a different pH buffered solution will result in a dramatically different measurement value from pH 7 being displayed in the event there is a hairline crack in the electrode.


Quick Cal Mode

Quick Cal mode allows the user to perform a single point pH and EC/TDS calibration with one solution. Simply enter calibration mode and the meter will prompt to confirm calibration to pH 6.86 and 5.00 mS/cm.


Multiparameter Measuring Modes

GroLine portable meters offer both Conductivity (EC) and Total Dissolved Solids (TDS) measuring modes. The EC measuring mode has an expanded scale to measure up to 6.00 mS/cm while TDS measuring range is up to 3999 ppm using a 0.7 conversion factor.


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Waterproof pH/EC/TDS Tester

Replaceable pH electrode with extractable junction

GroLine waterproof pocket pH/EC/TDS meter uses a cartridge design replaceable electrode that does not have any pins to align or that can be broken. Simply insert and turn to lock in place. The replacement pH electrode also has an extractable junction that is used to clear any clogging that occurs with use resulting in erratic and drifting readings.


Quick Cal Mode

Quick Cal mode allows the user to perform a single point pH and EC/TDS calibration with one solution. Simply enter calibration mode and the meter will prompt to confirm calibration to pH 6.86 and 5.00 mS/cm.


Multiparameter Measuring Modes

GroLine portable meters offer both Conductivity (EC) and Total Dissolved Solids (TDS) measuring modes. The EC measuring mode has an expanded scale to measure up to 6.00 mS/cm while TDS measuring range is up to 3999 ppm using a 0.7 conversion factor.


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pH Testers

More Options, More Choices

GroLine pocket meters include versions dedicated to only measuring pH. Meters include a choice of either an economical pH meter with a replaceable pH electrode or a waterproof slim line version that is remarkably easy to operate with only two buttons: one for turning the meter on/off and the other for calibration.


Big on Features and Affordable

GroLine pH meters feature automatic calibration, stability indicator, and automatic shut-off. Each of these features has their own benefits but the end result is a high performance meter that provides a precision laboratory measurement at an affordable price.


Replaceable pH Electrode Option

GroLine pH testers include a version with a screw type replaceable electrode. Based on care and use, the typical pH electrode will last 1-2 years. Replacing the electrode allows for an extended life for the meter.


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More Options, More Choices

GroLine pocket meters include versions dedicated to only measuring pH. Meters include a choice of either an economical pH meter with a replaceable pH electrode or a waterproof slim line version that is remarkably easy to operate with only two buttons: one for turning the meter on/off and the other for calibration.


Big on Features and Affordable

GroLine pH meters feature automatic calibration, stability indicator, and automatic shut-off. Each of these features has their own benefits but the end result is a high performance meter that provides a precision laboratory measurement at an affordable price.


Replaceable pH Electrode Option

GroLine pH testers include a version with a screw type replaceable electrode. Based on care and use, the typical pH electrode will last 1-2 years. Replacing the electrode allows for an extended life for the meter.


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EC/TDS Testers

More Options, More Choices

GroLine EC/TDS testers include both a standard handheld conductivity tester and a unique version with a pencil style conductivity probe for the direct insertion into soilless media. This handy meter can be used to monitor the salt build up of the growing medium to avoid burning plants with excess nutrients.


Big on Features and Affordable

GroLine EC/TDS testers meters feature automatic calibration, stability indicator, and automatic shut-off. Each of these features has their own benefits but the end result is a high performance meter that provides a precision laboratory measurement.


Multiple Measuring Modes

GroLine pocket meters include a version that offers both Conductivity (EC) and Total Dissolved Solids (TDS) measuring modes. The EC measuring mode has an expanded scale to measure up to 6.00 mS/cm while TDS measuring range is up to 3999 ppm using a 0.7 conversion factor.


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pH/EC/TDS Calibration Solutions

Quick Cal Dual-Purpose Calibration Solution

With GroLine Quick Cal solution only one solution is needed to calibrate both pH and conductivity. 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, respectively.


Supplied with Certificate of Analysis

All GroLine pH and Conductivity/TDS standards in a 230 ml bottle are supplied with a Certificate of Analysis (COA). The COA contains the information regarding the traceability of the solution to NIST traceability standard. Information includes Standard Reference Material (SRM) used for calibration, lot number, and date of production.


Right Size, Right Price

GroLine calibration solution is available in convenient 230 ml bottle size due to the frequency of use. Infrequent use would include users that calibrate and measure on a weekly or monthly basis. With infrequent use it is important that the solution be used within six months of opening the bottle. After that it should be changed out since the measurements will only be as good as the calibration solution, which degrades over time. For added convenience, the Quick-Cal Solution is also available in 20 ml sachets.


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Quick Cal Dual-Purpose Calibration Solution

With GroLine Quick Cal solution only one solution is needed to calibrate both pH and conductivity. 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, respectively.


Supplied with Certificate of Analysis

All GroLine pH and Conductivity/TDS standards in a 230 ml bottle are supplied with a Certificate of Analysis (COA). The COA contains the information regarding the traceability of the solution to NIST traceability standard. Information includes Standard Reference Material (SRM) used for calibration, lot number, and date of production.


Right Size, Right Price

GroLine calibration solution is available in convenient 230 ml bottle size due to the frequency of use. Infrequent use would include users that calibrate and measure on a weekly or monthly basis. With infrequent use it is important that the solution be used within six months of opening the bottle. After that it should be changed out since the measurements will only be as good as the calibration solution, which degrades over time. For added convenience, the Quick-Cal Solution is also available in 20 ml sachets.


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Cleaning and Storage Solutions

GroLine Cleaning Solution

Maintaining a clean pH electrode is vital for not only in getting an accurate pH measurement but also ones that are drift free. 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 ensures the maximum performance from the pH electrode to provide readings that you can depend on.


GroLine Storage Solution

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. GroLine storage solutions are specifically formulated to accomplish the task and maximize the life of the pH electrode.


Right Size, Right Price

GroLine calibration cleaning and storage solution is available in convenient 230 ml bottle size.


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