Dear HORIBA Technical Support,

We are currently experiencing difficulties when measuring the pH of pure water and ultrapure water. During measurements, the pH value does not stabilize and continues to fluctuate, making it difficult for us to obtain a reliable and repeatable reading.

Could you please recommend a suitable HORIBA pH electrode/probe specifically designed for pure and ultrapure water applications?

If possible, we would prefer a probe with a BNC connector, as this would be more convenient for our existing measurement setup.

Could you please advise us on:

The most suitable HORIBA pH probe for pure and ultrapure water measurements
Whether the recommended probe is suitable for low-conductivity water
Any specific measurement or calibration considerations for ultrapure water
The recommended reference system and filling solution, if applicable
Available BNC-connected models
The price of the recommended probe and any necessary accessories
We would appreciate your technical recommendation and a quotation for the most suitable model.

Thank you in advance for your support.