Swan pH electrode. Chematest 35

There is no buffer solution in the box; the electrode comes alone as a pH electrode/temperature sensor with cable and 4-pin connector-

pH measurement in public pools must be done with a pH electrode

Monitoring of swimming pools
4.4.1 Measurement frequency for pH 
The manual measurement should be carried out on site immediately after sampling. Continuous pH measurement should be performed on water immediately after it has left the pool. At the same measurement point, there should also be a sampling tap for daily manual measurement to check the automatic equipment. Measurements carried out by operating personnel must be performed using a pH meter or other automatic equipment that provides good reliability of the measurements. The colorimetric method (by comparing color in a comparator) cannot be used due to far too much uncertainty.