If the chlorine residual is above 5.0 ppm or the bromine residual is above 8.0 ppm, do not swim. High sanitiser levels can cause skin and eye irritation for some people.
Most of the time, high sanitiser levels will drop to normal fairly quickly, especially with warmer temperatures. If a high level of sanitiser has been maintained for several days without dropping, reduce the number of tablets or sticks being used or turn down the automatic feeder.
If the sanitiser supply has been lowered and the residual is still high, you may lower it by using Chem Out according to label instructions.