Bluelab pH Pen

Bluelab pH Pen

SKU #: HGC716480
Bluelab Brand Product

Availability: In stock

Lead time: This product ships in 7-10 Business Days

Shipment Restrictions - What's This?
This item cannot be shipped to the following states: AK, HI

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The Bluelab pH Pen is the most simple, user-friendly pH and temperature testing tool on the market. Testing your nutrient solution has never been this fast or easy. Simply turn the pen on, stick it in your solution, and read the pH/temp. For just over $100, you won't find a pH device this accurate, reliable, and simple!

Benfits Of Testing With The Bluelab pH Pen

If you have grown before, you understand how fickle plants can be sometimes. They'll only thrive under very specific conditions. One of the most important aspects of your grow you need to monitor is the pH and temperature of the nutrients you feed them. If these are out of whack, it will lead to issues with uptake.

Plants can only take up nutrients when pH is in a specific range between 5.5-6.5. Any lower or higher, and certain nutrients get locked out, presenting the possibility for deficiencies. A good way to look at it is the nutrients you feed your plant are a lock, and proper pH is the key!

The Bluelab pH Pen also measures the temperature of your solution, ensuring you don't feed a solution that is too hot or cold. This can also affect nutrient uptake, but also can contribute to issues such as mold or mildew in the root zone. When paired with the Bluelab ppm / EC Pen , you'll have access to all the metrics you need for ensuring your plants are thriving, and reach their full potential!

Bluelab pH Pen Features

  • Measures pH and temperature accurately and quickly
  • Selectable units for temperature - work in Celsius or Fahrenheit!
  • Backlit LCD display is easy to read
  • Double junction probe (not replaceable)
  • Successful pH calibration indicator
  • Hold reading function
  • Low battery indicator
  • Fully waterproof
  • Auto off function preserves life of the unit
  • Automatic temperature compensation
  • 1 x AAA alkaline battery included

Bluelab pH Pen Applications

  • Aquaculture
  • Aquaponics
  • Floriculture
  • Greenhouse
  • Hydroponics
  • Industry

Want to learn more about the importance and relationship between nutrients & pH ? Visit our learning center for the complete guide!.

Tech Specs


Weight (lb.)0.4
Height (in.)8.2
Prop 65No
Lead TimeThis product ships in 7-10 Business Days
Length (in.)1.9
Width (in.)3.7
Warranty1 Year
UL ListedNo
Shipping RestrictionsAK, HI

Bluelab pH Pen Videos

Product Q&A

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.


Bluelab pH Pen Reviews

always works great
as long as you keep it clean and maintained, it will last for years with no issues.

Old reliable
still working strong after 3 years

Good pen, not waterproof
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.