While spaying is traditionally recommended for kitties between 4 and 6 months of age, spaying as young as 8 weeks old is considered safe, according to Cat Channel.
The national drinking water standards state that the maximum residual amount of chlorine is 4 mg/L. Untill recently the USA used chlorine gas extensively for wastewater treatment. Today, the use of chlorine has been forced back.
You should shock if the combined chlorine is above 1 -2 PPM, at first signs of algae or loss of water quality or anytime the Free Chlorine level bottoms out. The absence of Free Chlorine can be the result of heavy bather usage, heavy rainfall or insufficient chlorine being added.