Description

The Bluelab pH 4.0 Calibration Solution is a buffer solution used to calibrate pH meters, pens, probes, and other pH measuring equipment. Calibration solutions are critical to ensure that your pH measurement tools give accurate and reliable readings — especially in applications like hydroponics, gardening, laboratory work, aquariums, and environmental testing.

• Designed to set the reference point at pH 4.0, which is used as the acidic calibration standard when performing two-point calibration of most pH meters. The meter is normally calibrated at pH 7.0 first (neutral) then at pH 4.0 to accurately define the instrument response curve.

• Made to high laboratory standards and typically referenced or traceable to recognized standard methods (e.g., NIST), ensuring accuracy and consistency in calibration.

• Regular calibration — especially before important measurement sessions or monthly — helps keep readings trustworthy and extends the useful life of the pH probe.

• Key Features

  • Essential for accurate pH measurement: Serves as a stable point to calibrate instruments so they read correctly at acidic pH.

  • Large 500 ml size: Suitable for repeated calibration sessions without frequent repurchasing.

  • Compatible with most meters: Works with Bluelab units and other brand pH meters that accept liquid buffer calibration.

  • Improves longevity and performance: Regular calibration helps maintain probe performance and meter accuracy over time.

   Tips for Use

  1. Two-Point Calibration: First calibrate your meter using pH 7.0 buffer, then use the pH 4.0 calibration solution to complete calibration for acidic range accuracy.

  2. Avoid contamination: Pour a small amount of buffer into a clean container for calibration — do not dip the probe directly into the main bottle repeatedly.

  3. Discard after use: Do not reuse the buffer you’ve used for calibration as it may become contaminated.