Ozone may not kill large organisms or remove inorganic chemicals, or heavy metals or large cysts, so these other items should be treated by filtration or other treatment prior to ozone treatment. Ozone is also effective in controlling color, taste, and odor problems. Ozone oxidizes manganese and iron into solid particles that can be filtered and eliminated.

Ozone treatment systems are usually installed as a primary point-of-entry sterilization system. Ozone will mix with the water, bubbles are created to ensure that the ozone is in contact with the untreated water. To have the most effective treatment, its best to have good turbulence and differential pressure. The water flow rate is important to size an ozone system.

Once the water flow rate is determined, then we determine the ozone contact time within the water to determine the most efficient effectiveness of ozonation. Ozone requires a shorter contact time than chlorine in most cases. Also in most cases, the lower the water temperature, the more ozone is dissolved in the water. Ozone is effective over a wide range of pH, but a pH above 7 increases the treatment efficiency. The amount of ozone required depends on the level of contamination in the water that needs to be treated. If substances in the water to be treated react with ozone, part of the ozone produced and injected in the water is used up, which will leave less ozone available to treat the targeted contaminants.