Grow Like Pro

equipment · Beginner

How to calibrate a pH meter

A clean workflow for calibration, storage, and verification.

By Grow Like Pro Editorial Team · Published · Updated · 1 min read

Botanical illustration of a healthy plant
Editorial botanical illustration.

Key takeaways

  • Use unexpired buffer in clean vessels.
  • Do not return used buffer to its bottle.
  • Store the electrode as its manufacturer directs.
On this page

Inspect first

Check the electrode for damage, adequate storage solution, and contamination. A dry or slow electrode may need conditioning according to its manual.

Calibrate

Pour small, fresh portions of the specified buffers into clean cups. Rinse the probe with deionized water, gently blot excess droplets, and follow the meter’s two-point calibration process. Never pour used buffer back.

Verify and store

Re-read a buffer as a check. Record the date and result. Rinse the probe and return it to the manufacturer-specified storage solution; typical glass pH electrodes should not be stored in pure water.

Sources

  1. University of Minnesota Extension: Small-scale hydroponics
  2. Oklahoma State University Extension: Electrical Conductivity and pH Guide