Sep 10, 2013 - When you're ready to make chlorine, a little salt-water electrolysis will . The key active ingredient in HTH Chlorinating Granules, calcium . Jul 2, 2017 - Chlorine isn't just used in swimming pools and bleach. It can be found in everyday household items like cleaners and diapers. Read why we . Many pool owners use household bleach, though it only boasts an Available Chlorine (active ingredient) level of 5% compared to Pool Liquid Chlorine of . Ingredients -- Synonyms. Chlorine tablets. Description. White powder or tablets. It is made by bubbling chlorine gas through a solution of calcium hydroxide. Uses. Calcium hypochlorite is the main ingredient in swimming pool chlorine tablets. State codes require that chlorine be injected into the pool water through the use of an approved cyanuric acid will have one of the following active ingredients:.