QI need further information about the water which can be used for experiments.
Generally there are four types of water for experiments: demineralized water, pure water, distilled water and ultra pure water.
The right choice of water depends on its intended use. The degree of water purity may be described as follows:
Demineralized water → Pure water → Distilled water → Ultrapure water.
Demineralized water: obtained by treating water with a hydrogen type which is a strongly acidic cation exchange resin and a hydroxyl type which is a weak basic anion exchange resin (from Chemical Dictionary)
Pure water: Purified by combination of distilled water, exchanging ion, or ultrafiltration (From the Japanese Pharmacopoeia) Distilled water: Obtained by distillation of desalted and purified water by cooling and collecting the generated water vapor (from the Chemical Dictionary) Ultrapure water: The purity of ultrapure water is higher than by the above mentioned three types of water.