Chlorine is the chemical of all pool chemicals. Understanding how to keep your pool chlorinated is the key to a sparkling clear pool. If you add too much chlorine to your pool will lead to more acid demand, raised pH, poor water clarity, and even calcium formations in your pool. In this case- more is not always better. 
Why is chlorine important? It is a vital part of your pool chemistry. Chlorine sanitizes the water and keeps it safe for swimmers. If you don’t have enough chlorine, or enough free chlorine, your water might be unsafe for swimming. The germs, bacteria, and even algae will thrive in these conditions and can create an unsafe swimming environment (not to mention costly damage).
If you find your pool water cloudy, it could be an issue with pH and chlorine activity. Check your pH levels to make sure those are all in balance. Sometimes cloudy water or high algae conditions can be solved simply by lowering the pH levels and not even adding chlorine!