Grow better with GroLine.
Meters and testers designed for hydroponic, aquaponic, and greenhouse growers to get consistently great results.
Hanna GroLine products are the most accurate and easiest to use tools to help you manage your growing nutrients.
Monitor like a scientist. Grow like a professional.
GroLine Hydroponic Nutrients Monitor for pH, EC, TDS, and Temperature - HI981420
Measure with confidence.
GroLine Waterproof Combo Meter for pH, EC, TDS (ppm) - HI9814
No time to waste.
Start testing faster with Quick Cal mode to perform a single point pH and EC/TDS calibration with one solution.
Developed to help growers test nutrients often and easily.
Take accurate and reliable nutrient measurements with our portable testers that go where you go.
Simple pH Tester
Conductivity & TDS (ppm) Tester
Direct soil measurements, simplified.
See what your roots see.
Direct Soil pH Electrode
Soil Conductivity Tester
HALO® Wireless Soil pH Meter
Bring it all together.
GroLine Waterproof Combo Tester for pH, EC, TDS (ppm)
More reasons to love GroLine.
Growers all over the world rely on GroLine products to ensure successful crop yields.
"Best Portable Meter"
I have been using this HI9814 daily for about a year now. I will never go back!
"This IS the meter for your needs"
Accurate testing is critical to appraising ones water to determine filtration needs. This is the one you want!! pH dead on, PPM/EC true as you can get!
"Love this product"
Absolutely love this product. Very accurate and easy to use. Will recommend this to everyone.
Perfect for testing directly in your soil or other growing media.
Direct Soil and Soilless Media pH Electrode for HI9814
This electrode was created specifically for pH measurements in soil, coco, rockwool, and water. With a built-in temperature sensor and automatic temperature compensation, you can feel confident that your results are right the first time.
Need a Replacement Electrode?
Providing solutions to the problems growers face every day.
How to Prepare a Soil Slurry
Not sure how to prepare a sample for pH and EC/TDS (ppm) testing? Follow these steps, or watch the video below!
Step 1: Gather your materials. You will need:
- A container cleaned with distilled or DI water
- A measuring cup
- A fresh sample of your soil
- Distilled or DI water
- A magnetic stirrer OR a stirring utensil
Step 2: Measure out equal parts of soil and distilled water, ensuring there is a large enough sample to completely submerge your electrode junction.
Step 3: Add soil to the clean container, then add the distilled water.
Step 4: Stir the sample. For best results, use a magnetic stirrer. Make sure all clumps of soil are broken up!
Step 5: Wait 15 minutes for the sample to settle before taking your measurement.
Step 6: Immerse your electrode into the sample and wait for a stable reading.
Hanna Tip: An ideal pH reading is between 5.5 and 7. If you are getting a reading far off from this, there may be a problem with your electrode. Check our pH Electrode Troubleshooting Guide for some common problems and how to fix them.
pH Testing Tips
Depending on the nature of your samples, your pH electrode can become dirty or clogged resulting in slow and faulty readings. Regular cleaning will prolong the life of your electrode.
To ensure your pH measurements are accurate, be sure to calibrate after extended storage, cleaning, and before use. Use fresh buffers that bracket your expected value.
A dry electrode results in slow, incorrect measurements. Always use proper storage solution and be sure to fully cover the junction.
To learn more, download our pH Best Practices Guide here!
Your pH Electrode
Pick the Right Tip Shape for Your Testing Needs.
A spherical tip is the most common shape for a pH electrode due to it's large surface area.
BEST FOR: aqueous samples and general purpose.
A cone shape makes testing of semi-solids easy.
BEST FOR: direct penetration into semi-solids, emulsions, soil, and slurries.
The flat tip allows for the direct surface measurement of a sample.
BEST FOR: flat surfaces, skin, leather, and paper.
Finding the right electrode for specific testing can be tough. In order to help, Hanna Instruments has put together a guide, Getting To Know Your pH Electrode.