Changes

: [[Fresh Water|Fresh water]] is the easiest to make '''potable'''. This is done by [[Filtration|filtering]] the [[water]] to remove [[solid]] [[particle]]s then adding [[Chlorine]] or using [[Ultraviolet Light]] to kill any harmful [[micro-organism]]s.

: [[Brine|Salt water]] must have the [[salt]] removed first. This can be done by [[distillation]] which also kills [[micro-organism]]s and [[pure|purifies]] the [[water]]. However, this is very expensive because it requires [[heat]]ing the [[water]]. It can also be done using a process called reverse osmosis in which the [[Brine|salt water]] is sent through pipes at extremely high [[pressure]]. The walls of the pipes are a [[Partially Permeable Membrane|partially permeable membrane]] and so the high [[pressure]] forces the [[water]] through but not the [[salt]].