
The tester is used to measure oxygen and pH levels in pool water. To keep your pool water crystal clear, using a tester is essential. Take a water sample from your pool, and if the measured values are outside the recommended range (pH 6.9-7.4; O2 3.0-8.0 mg/l), adjust them using pool chemicals. First adjust the pH value (pH+ or pH-), and then adjust the oxygen level (only increase it - if the chlorine level is too high, do not lower it; it will drop on its own after a few days). Oxygen should be added only after the pH has been regulated, because the effectiveness of oxygen drops rapidly outside the recommended pH range.
The DPD tester works on the principle of visual comparison with a color scale next to the sample chambers. After adding the Oxy/pH tablet to the chamber, the water changes color, and the Oxy/pH levels in the pool should be adjusted according to the result.