Optimize Your Plants' Nutrient Uptake with the Bluelab Digital pH & Temperature Pen

Ensure that your plants get the right minerals they need for optimal growth with the Bluelab Digital pH & Temperature Pen. By accurately measuring the pH and temperature of your nutrient solution, this top-quality pen helps you maintain ideal growing conditions for your plants, resulting in better nutrient absorption, improved growth rates, and robust overall health.

Features and Benefits

  • Measures pH and temperature: Simultaneously and accurately measures the pH and temperature of your nutrient solution, giving you complete control over your plants' environment.
  • Selectable temperature units: Choose between Celsius (°C) or Fahrenheit (°F) temperature units to suit your preference.
  • Double junction probe: Ensures accurate and stable measurements by preventing electrode fouling.
  • Automatic pH calibration: Calibrates your pH pen easily and quickly to maintain accurate measurements.
  • Fully Waterproof: Safeguards the pen from moisture, making it durable and long-lasting.
  • Wide measurement range: Measures pH levels from 0.0 to 14.0 and temperatures from 0 to 50°C.
  • Auto-off feature: Conserves battery life by automatically switching off the pen when not in use.
  • Battery included: Comes with 1 AAA battery for immediate use.
  • Made in New Zealand: Manufactured to high-quality standards to ensure top performance.
  • 1-year warranty: Enjoy peace of mind with this comprehensive warranty.

How to Use

  1. Hydrate your Bluelab pH Pen in storage solution for 24 hours before the first use.
  2. Calibrate the pH pen to pH 7 and then to pH 4 using the included calibration solutions.
  3. Turn on the pen by pressing the power button and measure the pH and temperature of your nutrient solution.
  4. Adjust the pH of your nutrient solution as needed to achieve ideal growing conditions for your plants.
  5. Rinse the probe with clean water after each use and add storage solution to the cap before replacing it.
  6. Calibrate the pH pen regularly to maintain accurate measurements.

Aqua Gardening Suggests These are Best For

The Bluelab Digital pH & Temperature Pen is best for hydroponic gardeners, aquarium enthusiasts, and those seeking to maintain ideal growing conditions for their plants, providing fast, accurate and reliable measurements to ensure optimal nutrient uptake and overall plant health.

Notes from Aqua Gardening

  • Read the instruction manual before using the Bluelab pH Pen to ensure proper usage and care.
  • Hydrate and calibrate the pH pen before the first use and regularly thereafter for accurate measurements.
  • Do not continuously submerge the pen in the water reservoir and avoid dropping it as this can damage the pen.


How does the Bluelab Digital pH & Temperature Pen benefit my plants?

The Bluelab Digital pH & Temperature Pen provides a precise and convenient way to manage the pH and temperature of your nutrient solution. By ensuring optimum pH and temperature conditions, your plants will be able to absorb the necessary minerals for maximum growth and health.

What sets the Bluelab pH Pen apart from cheaper alternatives?

While cheaper pH pens may work well initially, they often fail to provide accurate readings or proper calibration over time. The Bluelab pH Pen is a high-quality, durable and accurate tool that ensures consistent and reliable results in measuring pH and temperature.

Can the Bluelab pH Pen measure temperature in both Celsius and Fahrenheit?

Yes, the Bluelab pH Pen allows you to switch between Celsius and Fahrenheit temperature measurements by holding down the Units button for 3 seconds.

How often should I calibrate my Bluelab pH Pen?

You should calibrate your pH Pen before its first use, after 30 days of use, if the reading is different than expected, after cleaning and hydration, and after changing the batteries.

How do I maintain my Bluelab pH Pen for optimal performance?

To maintain your Bluelab pH Pen, follow these tips:

- Read the manual

- Use probe storage solution in the cap

- Keep the cap on when not in use

- Calibrate regularly depending on your level of use

- Do not continuously submerge it in the water reservoir

- Avoid dropping the pen as it can crack if knocked hard enough

By following these guidelines, you can ensure your pH Pen will last for many years of use.

What is included with the Bluelab pH Pen?

When you purchase a Bluelab pH Pen, you will receive the following items:

- Bluelab pH Pen

- pH 4 Buffer Solution 20ml

- pH 7 Buffer Solution 20ml

- Storage Solution (KCl) 20ml

Still Unsure if This Product is Right for You?

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Product Manual

View PDF brochure for Bluelab Digital pH & Temperature Pen

(SKU: 124259)

Simple to clean, Waterproof Cable Joint, Double junction, A good BNC connection, Gel Filled (Non-Refillable), Probe Holder Included (Keeps probe secure)

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1 Year Replacement Warranty - Store warranty, this product needs to be returned to Aqua Gardening for testing and replacement.


60 Day Returns - We will provide a refund, exchange or store credit where you have decided you no longer want the product and it is in new, unopened condition. More details...