Astralpool pH Probe Calibration: Problem and Proposed Solution

Client:
Hello, I am calibrating my Astralpool pH probe. My pump indicates that it is calibrated to 7.0, but when I put it back in place, it goes up to 9.9.

Technical Advisor:
Hello

Technical Advisor:
Please try this quick test https://ph-redox-pool.com/gb/content/16-ma-sonde-ph-est-elle-hors-service-

Client:
Thank you, I will try it and come back to you. Regards, Christophe

Technical Advisor:
Have a great day