Generally, as temperature increases chlorine becomes more active as a disinfectant. However, raising the temperature increases the ability of organic matter to tie-up chlorine. In addition, raising the temperature also speeds up the loss of chlorine into the atmosphere. A minimum of 15 minutes of exposure to chlorine is required for adequate disinfection. However, efficient disinfection depends upon accurately monitoring the concentration of chlorine in the tank.
Treatment is most effective when chlorine is metered continuously.
It is ineffective to simply dump chlorine into the tank. For fungi an effective concentration of 500 ppm of free chlorine is required. If the concentration of chlorine is too high, or if the pH of the chlorine solution is too low, chlorine gas is wasted into the air. This creates an odor problem, wastes chlorine, and corrodes equipment. It is better to meter in the chlorine and control the pH of the solution than to double the amount of chlorine in the solution.