Reverse osmosis

=== Remineralisation and pH adjustment ===
The desalinated water is stabilized to protect downstream pipelines and storage, usually by adding [[Lime (material)|lime]] or [[Sodium hydroxide|caustic soda]] to prevent corrosion of concrete-lined surfaces. Liming material is used to adjust pH between 6.8 and 8.1 to meet the potable water specifications, primarily for effective disinfection and for corrosion control. Remineralisation may be needed to replace minerals removed from the water by desalination, although this process has proved to be costly and inconvenient in order to meet mineral demand by humans and plants as found in typical freshwater. For instance water from Israel's national water carrier typically contains dissolved magnesium levels of 20 to 25&nbsp;mg/liter, while water from the [[Ashkelon]] plant has no magnesium. Ashkelon water created [[Magnesium deficiency|magnesium-deficiency]] symptoms in crops, including tomatoes, basil, and flowers, and had to be remedied by fertilization. Israeli drinking water standards require a minimum calcium level of 20&nbsp;mg/liter. Askelon's post-desalination treatment uses sulfuric acid to dissolve calcite (limestone), resulting in calcium concentrations of 40 to 46&nbsp;mg/liter, lower than the 45 to 60&nbsp;mg/liter found in typical Israeli fresh water.