Is hard or soft water better at removing dirt and bacteria?
• The difference hard water makes to the effectiveness of washing depends on the type of hardness, dirt and detergent. As a rule of thumb, hard water interferes with cleaning because it contains dissolved salts that cause some common kinds of detergent to precipitate out, more or less gluing down grit, grease and other dirt, especially in corners, cracks and on rough surfaces.
If the dirt is full of harmful microbes, then they become hard to remove or to expose to disinfectants and sterilising ultraviolet. This is especially true for…
