Calibrating your pH meter

You cannot simply turn on a meter and measure accurately. You must perform a 2-point calibration that "brackets" your target. 

Measuring below 7.00 pH

1. Clean: Rinse the probe with distilled water.

2. Point A (Neutral): Calibrate with pH 7.00 buffer solution first.

3. Point B (Acid): Calibrate with pH 4.00 buffer solution second.

   • Note: Do not use pH 10.01 buffer. Your target must be between the two calibrated points (4 and 7) for the math to work correctly.

Measuring above 7.00 pH

1. Clean: Rinse the probe with distilled water.

2. Point A (Neutral): Calibrate with pH 7.00 buffer solution first.

3. Point B (Basic): Calibrate with pH 10.00 buffer solution second.

   • Note: Do not use pH 4.00 buffer. Your target must be between the two calibrated points (7 and 10) for the math to work correctly.