calcium hypochlorite 200g tablet for swimming pool

Sodium and calcium hypochlorite are disinfectants used in bleach and bleach products, purifying drinking water, swimming pools, ponds and wastewater. Sodium and calcium hypochlorite also are used in soil treatment of fruits and vegetables. Hypochlorites control bacteria, fungi and slime-forming algae that causes disease in people and animals. In the presence of oxygen, the hypochlorites convert readily into sodium chloride (table salt) and calcium chloride (road salt). 
 

Drinking Water
The EPA's Office of Drinking Water has tested sodium and calcium hypochlorite thoroughly for water and wastewater systems to make sure they do not create carcinogens. The EPA set a maximum contaminant level of 100 parts per billion in drinking water.

Calcium hypochlorite chlorine is one of the most commonly available swimming pool water disinfectants. It's also very high in free available chlorine, which can be a bleaching agent. And though it doesn't itself cause pitting in the concrete of a concrete swimming pool, there are a couple of other issues. For one, its high chlorine levels can discolor a pool's painted surfaces. For another, inadequate levels can help contribute to the onset of calcium carbonate scale

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