Have you ever questioned if deionized water can be used in place of the distilled water recommend for use when making a plating bath from a concentrated solution, replacing water evaporated from an existing bath or for use as rinse water?
Is there a real difference in the type of water you use?
The answer is yes. There are many types of water available today and the quality varies greatly. First and foremost never add tap water to your solutions or use it for rinsing. It contains minerals and chemicals like chlorine and fluorides. It’s processed for drinking and far from the purity needed for electroplating. Bottled drinking water, no matter how “pure” the label says it is, is another poor choice. It too is made for drinking and many have added minerals to make it taste better.
This brings us to the question of distilled water or deionized water.
Distillation will remove minerals and bacteria and many organics, but may not remove all oils and VOCs (volatile organic chemicals) from the water as they can carry over in the steam. Deionization removes minerals, oils, and VOCs but will not remove bacteria, sugars and other organics. Past arguments have been made for and against the use of both types of purification methods when electroplating making the choice a confusing one. The good news is commercially available distilled and deionized water are now made using multistage purification systems.
Activated charcoal filters, ultraviolet sterilization and other methods are used to eliminate the bacteria, VOCs and organics left behind by single step purification methods. So either distilled or deionized bottled waters are well-suited for you electroplating needs.
Remember to keep the bottles closed after opening, store away from direct sunlight and heat, and change your rinse water regularly.