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OTO Test Kits
6 ResultsOTO Pool Water Test Kits
OTO test kits use a liquid chemical OTO (orthotolidine) that causes a color change to yellow in the presence of total chlorine. Using a comparator, you would look for the color change. OTO is recommended for pools that are sanitized using Bromine. This method only measures total chlorine and is not permitted to be used at regulated facilities. It does not measure free chlorine.