This is a testing liquid for the measurement of total chlorine or bromine levels using the Titration (drops) method. Maintaining your hot tub at the correct chlorine and bromine level keeps your water clear, free of bacteria and helps extend the life of your hot tub equipment.

The optimum bromine level is 3–5 parts per million (ppm) and the chlorine level should stay between 1.0 and 3.0 parts per million (ppm).
OTO Reagent is used in Beachcomber’s chlorine and bromine test kits.

To properly titrate (apply drops) while testing, reagent bottles need to be fully vertical during titration to ensure that the correct drop is produced.