How do I measure the amount of Lotus Clean Shock with the Poollab photometer? Am I right in assuming that Lotus Clean Shock is measured as chlorine dioxide? If this is the case, my question would be up to which concentrations the water may be used or reused after application? The values in the Poollab are given in ppm for chlorine dioxide, but in mg/l with the Shock test strips in "Shock|ph" from my whirlpool supplier. When I added 65 ml Lotus Clean Shock to 1300 l water in my pool this morning, I had a value of 1.47 ppm ClO2 after half an hour with the Poollab photometer using the chlorine dioxide measuring method. With the test strips, the value was 0.3 mg/l. For both methods, the limits for use/reuse would be of great interest.
Lotus Clean Shock contains two types of chlorine which react with each other in the whirlpool when they come into contact with the water and permanently produce chlorine dioxide. This is why Lotus Clean Shock can be measured with any chlorine measuring device. You can therefore measure the free chlorine with DPD1 and the total chlorine with DPD3. And from this difference the combined chlorine.
You cannot measure the chlorine dioxide. Due to the presence of free chlorine, combined chlorine and chlorine dioxide, the measurement results for the chlorine dioxide are falsified.