24/09/2026
💧 Why does hard water affect dishwasher results?
If you’re finding spots, streaks or a pale film on your glasses and crockery, hard water could be part of the picture.
When hard water is heated, calcium and magnesium can contribute to mineral deposits and limescale. As water droplets dry on your dishes, those minerals can also be left behind — creating those familiar cloudy spots and films.
But poor results don’t necessarily mean your dishwasher detergent isn’t working.
The final result depends on a combination of factors, including:
✨ Your water hardness
✨ The dishwasher’s water-softening setting
✨ Dishwasher salt
✨ Rinse aid
✨ The programme you use
✨ How the machine is loaded
Hard water can also contribute to deposits building up inside your dishwasher over time, which is why it’s important to make sure your machine is correctly set up for your local water supply.