Two types of chemicals used to disinfect swimming-pool water are calcium hypochlorite and chlorinated isocyanurate. These pool chlorinating chemicals are sold in various forms under number of different trademarks. 

1- Inorganic chlorine (Not Stabilized Chlorine):

Chlorine gas (Gas)

Sodium Hypochlorite (Liquid)

Calcium and the lithium Hypochlorite (Solid)

2- Organic Chlorine  (Stabilized Chlorine):

Sodium dichloisocyanurite acid (Solid)

Trichloroisocyanurite acid (Solid)

1- Directly to the pool water.

Ensure the filtration equipment is switched off and the pool empty of the bathers before adding products.

Pour the necessary dose of product in a container with water and evenly distribute over the pool water surface.

2- With Skimmer.

Place the quantity necessary of product in the skimmers baskets, once the filtering equipment has been backwashes.

3- Inject of recirculating water.

With the filtering equipment working, inject product, by means of a metering pump, before entreating the filters.

Swimming pools require care and maintenance to keep them in a perfect state of clearness and disinfection.

Bathers and the environment (Wind, rain,  etc) introduce into the swimming pool  water micro-organism and contaminants which could harm users and cause deterioration in the facilities. Filtering helps to eliminate a large part of dirt which has been introduced, but the growth of bacteria, algae and viruses can only be prevented by adding chemical products.