Shock Treatment Chart is a visual aid that is used to monitor and track the levels of chemicals in swimming pools and spas. The chart typically displays the recommended levels of chemicals such as chlorine, pH, alkalinity, and calcium hardness, and guides how to adjust these levels if they fall outside of the recommended range. Shock Treatment Chart is often made of durable materials such as laminated paper or plastic and can be affixed to the side of a pool or hot tub for easy reference.