Bluelab Meters and Monitors

Understanding the nutrient solution is an important part of successful growing. Growth Technology’s accurate range of Bluelab meters and testing equipment make this task quick and easy.

Bluelab pH Meter®

When measuring the pH of a solution is important… reach for the Bluelab pH Meter.

The Bluelab pH Meter is used to accurately measure the pH value of a solution.

Simply place the Bluelab pH probe into the solution and the reading will be displayed on the screen. As the meter is portable and does not need a power supply to operate, it can be used anywhere and anytime to help you manage your crops’ daily nutrient requirements.

Calibration is simple with the push buttons on the meter and fresh Bluelab calibration solutions.


  • Lightweight and portable
  • Large easy to read display
  • Simple push button pH calibration
  • Replaceable double junction pH probe included
  • Successful pH calibration indicator
  • Over range and under range indicators
  • 2 x AAA alkaline batteries included
  • Auto off function
  • Low battery indicator

bluelab 5 year..

  • Rinse the Bluelab pH Probe after each use.
  • Clean and calibrate the Bluelab pH Probe when: 1) The reading is different to what was expected. 2) The batteries have been removed or changed. 3) The calibration indicators have disappeared. 4) The Bluelab pH Probe is replaced with a new one or is disconnected from the Bluelab pH Meter.
  • Calibrate the Bluelab pH Probe in fresh calibration solutions. Large bottles of calibration solution should be decantered into small plastic containers. This stops contamination of the solution.
  • Use Bluelab calibration solutions to calibrate the pH where possible. They have been specially created to work with the Bluelab product range. Not all calibration solutions are created equal!
  • Calibrate the Bluelab pH Meter using the pH 7.0 calibration solution first, then the pH 4.0 solution.
  • Be gentle with the Bluelab pH Probe as they are glass and easily broken.
  • Be patient with pH. While calibrating or taking readings, wait until the reading has stabilized to a constant value.
  • Place the Bluelab pH Probe storage cap filled with fresh water or Bluelab pH Probe Storage Solution back over the tip of the Bluelab pH Probe when not in use. This stops the Bluelab pH Probe from drying out. If it dries it dies!
  • Remove batteries and disconnect the Bluelab pH Probe if the Bluelab pH Meter is to be stored for long periods of time.
  • Use alkaline batteries where possible.
  • Store in a clean dry place out of direct sunlight.
  • Don’t be rough with Bluelab pH Probe or bang it on the side of the tank – it will break!
  • Don’t touch the Bluelab pH Probe tip with fingers. This will contaminate the probe surface.
  • Don’t use de-ionized or distilled water in the storage cap for the Bluelab pH Probe.
  • Don’t rinse the Bluelab pH Probe in de-ionized or distilled water
  • Don’t use rechargeable batteries.
  • Don’t submerse or drop the Bluelab pH Meter into any liquid, as it is not waterproof. If it is dropped in to water, immediately remove the batteries and place in a dry warm place for 24 hours.
  • Don’t throw away the Instruction Manual. Keep it in a safe place so it can be referred back to, if needed. The cleaning and calibration instructions are in the manual and should always be referred to until the grower is confident that the procedure is being carrying out correctly.
  • Don’t open the Bluelab pH Meter – there are no user adjustments inside. This will void the guarantee. It will show if it has been opened!

The two main effects the pH level has on plant growth is related to the availability of plant nutrients or the soil concentration of plant-toxic minerals. Within highly acid soils, micro-nutrients such as aluminium and manganese can become more available and therefore more toxic to the plant. Equally affecting growth when there are low pH values, calcium, phosphorus and magnesium are less available to the plant. ….Read more

ph probe is Contaminated – Clean ph Probe (see advice tab)

Incorrect Calibration – Ensure calibration solutions are accurate. Replace if in doubt. Wait longer for readings to stabilize before calibrating to a constant value

Calibration unreliable – Calibrate pH probe

pH probe damaged or old – Replace pH probe

There is insufficient power to take a reading. Replace the batteries at once. DO NOT use rechargeable batteries.

It is likely that the batteries are dead or inserted incorrectly. Check batteries are correctly inserted and replace if necessary

This indicates a problem with the pH calibration. Please read ‘Section 11’ in the BlueLab Soil pH Meter Manual (error message descriptions)

While in pH mode – it is over or under the pH range, therefore the solution is > 14.0pH or solution is < 0.0pH. Check the pH probe connection, if this is connected correctly and problem still arises then the pH probe could be faulty.

Plant Lifecycle

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