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Bluelab pH Pen

Item #: 716480

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Bluelab pH Pen

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The ultimate handy solution for measuring pH and temperature!

Plants get their nutrient from minerals but they can only get all the right minerals they need if certain conditions are right. Think of nutrients like a lock. pH is the key. A key factor that affects food uptake is whether your solution is acid or alkaline. We measure this in pH.

The Bluelab pH Pen also measures the temperature of the solution, as root health is vital to the success of a crop. Temperature affects the growth rate and structure of a plant so a solution temperature of 18 - 22 degrees C or 65 - 72 degrees F is recommended.

The hand held pH pen provides a compact quick and handy way to manage the success of your crop to ensure maximum uptake of nutrients.

Teamed with our Bluelab ppm or EC Pen, you have a handy, convenient and accurate system for ensuring optimum plant growth and health.

  • Measures pH and temperature
  • Selectable units for temperature
  • Backlit LCD display
  • Double junction probe (not replaceable)
  • Successful pH calibration indicator
  • Hold reading function
  • Low battery indicator
  • Fully waterproof
  • Auto off function
  • Automatic temperature compensation
  • 1 x AAA alkaline battery included
  • 1 year guarantee for Bluelab pH Pen

Why is measuring pH vital to the success of your crop?
Plants eat. They get their nutrition from minerals but they can only get all the minerals they need if certain conditions are right. A key thing that affects food uptake is whether your solution is acid or alkaline. We measure this in pH. The clever little pH pen ensures you maintain the optimum pH reading that allows nutrients to be available to your plants.
Once you have measured the pH using the Bluelab pH Pen and know your plants can get at the food, you then then to measure how much food is available. This is referred to as conductivity and is measured by either ppm or EC. This is where the Bluelab ppm Pen comes in.


Brand Bluelab
SKU 716480
Weight (lb.) 0.32
Height (in.) 1.26
Length (in.) 9.84
Width (in.) 2.16
Warranty Yes
Free Shipping Yes
UPC 9421024920234
ETL Listed No
UL Listed No
CSA Listed No

Bluelab pH Pen Videos

Bluelab pH Pen Questions & Answers

I am unable to successfully calibrate my pH pen

Possible Reasons:

  • Buffers inaccurate
  • Glassware not clean
  • Glassware aged (glassware will not clean)
  • Probe not hydrated

Possible Solutions:

  • Replace buffers
  • Clean glassware
  • Replace unit
  • Soak probe in water for 24 hours and retest

What if my pH Pen or pH Probe has accidentally dried out?

The pH pen or probe must be 'hydrated' for 24 hours. Place the pH probe or pH pen upright in a small plastic container. Add enough KCl storage solution into the container to cover the pH probe tip. Leave the pH pen or pH probe to soak in the KCl solution for at least 24 hours.

Carry out a calibration to check if the pH pen or pH probe has already suffered permanent damage.

What is KCl storage solution?

KCl storage solution is generally a mixture of Potassium Chloride (KCl) and water. Some brands may contain small amounts of other ingredients.

Customer Reviews

Good pen, not waterproof Review by Honkey3k
I am on my second pen because the first stopped working properly after a few weeks. The second started acting up as well. I believe the unit is not meant to get wet except the very tip. When water gets into the seam at the top of the unit, it causes a problem. Not a bad pen but I wish it was waterproof.

(Posted on July 24, 2014)
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