Demineralised water is specially purified water that has had most or all of its mineral and salt ions removed, such as Calcium, Magnesium, Sodium, Chloride, Sulphate, Nitrate and Bicarbonate. It is also known as Deionised water, DI or Demin water.
Demineralized water is generally defined as having between 1-10 mg/L (ppm) of total dissolved solids (TDS).
The major differences are that demineralised water is usually freer of mineral ions, depending on the number of processes used to make it, and distilled water may have less organic contaminants, as deionisation does not remove uncharged molecules such as viruses or bacteria.