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Dealing with limescale – hard water tips for your dishwasher

What is hard water and why is it ruining your dishwasher? We explain the causes of limescale and share our tips on combatting the effects of hard water with the right dishwasher additives. Spoiler: living with hard water is not that hard!

What is limescale? What does hard water mean?

In short, limescale is the visible result of hard water. You will see it if there is a white residue on glasses after the dishwasher, if you regularly find water spots on dishes and if there is a grey or white buildup around the door of your dishwasher. If you spot these tell-tale signs, you’ll know you have hard water. What does that mean? If you are living in a hard-water area, the water that comes out of your tap has a high mineral content because it was filtered through limestone and chalk. The fine magnesium carbonate and calcium carbonate particles filtered from these rock layers are suspended in regular tap water and are in no way harmful to us. They are, however, bad for home appliances, such as your kettle, washing machine and dishwasher – if you allow them to build up to limescale. If you aren’t sure whether you have hard water … then you probably don’t, but you can check with your local council, who will tell you the exact hardness level for your area. 

How to prevent limescale with dishwasher salt

The best way to deal with hard water is to prevent it from building up to limescale in the first place. Depending on how hard your water is, Somat products offer different levels of limescale protection. Dishwasher detergents with multi-active formulas already contain dishwasher salt, which is sufficient up to a certain level of water hardness. They protect your machine against limescale buildup and prevent white residue on glasses as well as water spots on dishes up to 21° dH (degrees of hardness).

However, if your water is harder than this or you are using a detergent without salt, you will need to add salt separately. Although chemically it is sodium chloride, just like table salt, you can’t use regular table salt in your dishwasher, as its fine grain could damage your dishwasher. Dishwasher salt softens the water by attracting the fine magnesium and calcium particles and preventing them from depositing on dishes, glasses or dishwasher parts. It comes in a large package, which is deposited into the designated softener unit, located on the metal base of the dishwasher underneath the bottom shelf. It may look like a small container once you unscrew the cap, but keep on pouring – you’ll be amazed how much salt it can hold. Don’t worry, if the softener unit is filled with water. The salt has to mix with water and dissolve to work its magic.

How to remove limescale with descaler

Now you know how to prevent limescale in your dishwasher, hopefully you’ll never have to deal with hard water problems again. Unless, of course, you have a cupboard full of glasses with that nasty white residue and dishes with water spots on them. The good news is that these will come out sparkling clean the next time you wash them with your new Somat's dishwasher caps/gel or once you start adding dishwasher salt to your machine. The bad news is that limescale buildup on your machine isn’t quite so easy to remove. If you notice thick, hard layers of limescale within the machine, use Somat machine cleaner to remove it and prevent it damaging your machine. It’s a good idea to use them once a month to make sure hard water doesn’t cause any damage to your dishwasher.

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