Blonde Girl Undresses Her Blue Swimsuit Outside At The Swimming Pool

Chemical disinfectants such as chlorine, bromine or mineral sanitizers, and additional filters are often used in swimming pools to prevent growth and spread of bacteria, viruses, algae and insect larvae. Alternatively, pools can be made without chemical disinfectants by using a biofilter with additional carbon filters and UV disinfection. In both cases, pools need to be fitted with an adequate flow rate.
History
The "Great Bath" at the site of Mohenjo-Daro was most likely dug during the 3rd millennium BC. This pool is 12 by 7 meters, is lined with bricks and was covered with a tar-based sealant.