Does hard water cause limescale and can water filters remove it?

If you've ever noticed a chalky residue in your kettle or a cloudy film on your glassware, you're likely dealing with hard water. As rainwater, among other sources, travels through the ground and into our taps, it collects minerals like calcium and magnesium. While naturally occurring, they can contribute to water hardness, an issue that affects not only the taste and clarity of your drinking water but also the efficiency and lifespan of your appliances.

For those living or working in hard water areas, limescale build-up is a familiar and frustrating problem. The harder the water, the more limescale you're likely to find clogging pipes, coating heating elements, and driving up energy bills.

But how does hard water cause limescale? In this blog, we’ll explore the science behind limescale formation, the risks it poses to your home and business, and how the right filtration technology can help you protect your investment while delivering cleaner, better-tasting water.

What is limescale in tap water?

 

Limescale is a chalky, white residue that forms when water containing high levels of calcium carbonate is heated. As the water boils, its ability to hold these minerals decreases, causing them to precipitate and settle as solid deposits. This is why limescale tends to build-up in kettles, coffee machines, and hot water systems – anywhere water is regularly heated.

Because limescale forms primarily through heating, it's rarely visible in cold tap water or bottled water stored at room temperature. However, its effects can be noticed over time through reduced appliance efficiency, increased energy use, and shortened product lifespans.

What is the difference between hard water and soft water?

The distinction between hard and soft water comes down to mineral content, and specifically, the concentrations of calcium and magnesium ions. Hard water contains higher levels of these minerals, while soft water has lower concentrations, either naturally or through treatment processes.

In the UK, around 60% of households have hard water. For those living in these areas, the presence of limescale in the local water supply can be a costly issue. Over time, it can lead to clogged pipes, stained fixtures, and decreased performance of household appliances, as well as the need for more frequent maintenance.

Is limescale in tap water bad for you?

Despite its unsightly appearance, limescale is not harmful to your health. The minerals responsible for limescale – calcium and magnesium – naturally occur in drinking water and are essential nutrients for the human body.

All tap water in the UK is subject to strict government regulation to ensure it remains safe and healthy to drink. So while limescale might leave chalky marks in your kettle or a film on your glassware, it poses no risk to your wellbeing. In fact, many people can benefit from the calcium and magnesium it contains.

What about appliances?

The same can’t be said for your appliances. Limescale build-up forces kettles, coffee machines, and other water-heating appliances to work much harder, reducing their energy efficiency and potentially shortening their lifespan.

Moreover, limescale leaves unflattering white marks on taps, sinks, shower heads, and tiles, particularly in bathrooms and kitchens, even in the cleanest homes or commercial spaces.

If your water supply is hard, the likelihood of experiencing these issues increases significantly. You can read more about hard water in our recent blog ‘How does water hardness affect water quality?’.

How to remove limescale from tap water

 

If you’re already dealing with limescale build-up on taps, kettles, or other surfaces, the good news is that it can be removed easily using mild acids. Common household liquids such as white vinegar or lemon juice are effective and affordable solutions for breaking down and dissolving limescale deposits.

While this method works well for surface-level removal, it’s important to note that cleaning only treats the symptoms. To reduce or eliminate limescale before it forms, especially in appliances that heat water, a proactive solution is needed at the source.

In the next section, we’ll explore how water filtration systems, including those offered by Zip Water, can help prevent limescale build-up, protect your appliances, and improve water quality over the long term.

Do water filters remove limescale?

High-quality water filtration systems can significantly reduce limescale and, in many cases, prevent it entirely. While not all water filters are designed to tackle hard water minerals, more advanced filtration systems like those used in the HydroTap range go beyond basic filtration to actively target the root cause of limescale.

Protect your drinking water solution with HydroCare

To keep your drinking water system performing at its best, ongoing care and maintenance are essential. That’s why we offer HydroCare – a comprehensive range of service plans designed to maintain peak performance, safeguard water quality, and extend the life of your HydroTap or filtered water system, including brands outside of Zip.

Our HydroCare packages include:

• Routine servicing to keep your system running efficiently

• Regular filter replacements for consistently clean, great-tasting water

• Performance checks to prevent issues before they arise

• Priority support from our expert service team

With HydroCare, you can enjoy the convenience of filtered boiling, chilled, or sparkling water – without the hassle of limescale build-up or unexpected maintenance.

Zip's limescale filtration kit

As part of HydroCare, if you're based in a hard water area, we will include limescale management in your package. Our kit is engineered to reduce calcium and magnesium, the key minerals responsible for limescale build-up. By softening the water before it enters the system, our kit helps to: 

• Prevent scale from forming inside the boiling and chilled water components

• Improve energy efficiency

• Extend appliance lifespan

• Preserve water taste and clarity

Combined with the state-of-the-art filtration built into HydroTap, our limescale management is for those in hard water areas or with high appliance usage, especially in commercial or high-demand settings.

By filtering out limescale at the source, you’re not just protecting your equipment – you’re ensuring consistently clean, high-quality water with every use.

In commercial environments like offices, hospitality venues, and healthcare settings, this is particularly important. Limescale doesn’t just affect taste and appearance. It increases maintenance costs, energy use, and downtime.

With the integrated limescale filters, limescale management kits, and HydroCare support, you get peace of mind – and consistently high-quality, great-tasting water without the damage hard water can cause.

How Zip Water can help

In today’s fast-paced world, it’s worth investing in solutions that prevent problems before they arise, even more so when it comes to something as essential as water. HydroTap is designed with built-in filtration that actively reduces the hardness of water, helping to minimise limescale formation without stripping away the healthy minerals your body needs, like some reverse osmosis filters.

By reducing calcium and magnesium to optimal levels, Zip Water systems help protect your appliances, improve water taste, and cut down on time-consuming maintenance, all while supporting your health and wellbeing.

From convenience and taste to health and wellbeing, water can significantly affect productivity in your workplace team. You can read more about why water filtration is important for health and wellbeing, to discover the benefits of installing a Zip Water tap in your workplace.

Whether you're upgrading your office hydration station or looking for a smarter solution at home, Zip Water offers a range of advanced systems that combine performance, sustainability, style, efficiency, and peace of mind.

Browse our drinking water solutions and start your free trial today.