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OTO Test Kits

6 Results
Express Ship
PoolMaster 5-Way Test Kit
5 (2)
Poolmaster #945-22260
66 in stock
Express Ship
All-In-One 4-Way Test Kit 78HR OTO (High-Range)
4.7 (3)
Pentair #R151186
15 in stock
Express Ship
2 in 1 pH and Chlorine OTO Test Kit
5 (1)
Pentair #R151076
Allow 3-6 Weeks to Ship
2 in 1 Bromine and pH Test Kit OTO
Pentair #R151196
Allow 1-2 Months to Ship

OTO 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.