What Does Hard Water Mean for Your Home and How Do You Treat It?

What is hard water and how do you treat it?

White, chalky marks on taps are often the first clue. Then the kettle starts scaling up and tea and coffee can look cloudy once poured. Even after cleaning, the shower screen looks dull again.

That’s hard water showing up in everyday places.

Hard water simply means the water contains higher levels of naturally occurring minerals, mainly calcium and magnesium. The NHMRC Australian Drinking Water Guidelines explain that higher mineral content can change how water tastes and behaves, even though it remains safe to drink.

Western Australia relies more heavily on groundwater sources than most east-coast areas. As water moves through mineral-rich soil and rock before reaching the mains supply, more calcium and magnesium dissolve into it. 

This is why, according to the Water Corporation, mains water in Perth and across WA is generally harder than water supplied to east-coast areas which mostly draw from surface water catchments.

Although it is safe to drink, the higher mineral content can cause scale on taps, kettles and appliances, make soap and shampoo harder to lather, and force heating elements in hot water systems to work harder.

Is Perth water hard?

Yes. Perth water hardness comes from elevated calcium and magnesium in the mains supply. Much of that mineral content comes from groundwater sources, including the Gnangara groundwater system, which draws through mineral-rich aquifers.

If you have moved from Melbourne or the east coast, you will notice it quickly. Water feels and tastes different, you need to use more shampoo, and scale appears faster than expected.

In the Pilbara, including Karratha, Tom Price, Onslow and Paraburdoo, water supplies rely more heavily on local groundwater and surface sources. These pass through mineral-rich geology, which results in even harder water.

In regional parts of Western Australia, water filter systems have to work harder to remove the additional minerals and sediment, and scale can build more quickly than in many Perth metro homes.

Water2water has worked with Perth, Pilbara and regional WA water conditions for 25 years. Our local knowledge and experience mean we understand how to assess and treat hard water in WA homes.

Signs of hard water at home

Most people notice the signs of scale buildup before they know the cause. Ugly marks on your bathroom tiles and shower screen, crusty white marks on taps and cloudy water from the kettle are common signs.

In kitchen appliances, scale builds up on heating elements in hot water systems, coffee machines, dishwashers and washing machines. It creates an insulation layer that forces appliances to work harder, use more energy, cause a drop in water pressure, and reduce a product’s lifespan.

In the bathroom, hard water scale buildup doesn’t just cause unsightly stains on shower screens, taps, and tiles. It can also leave your skin and hair feeling dry and sensitive.

Does a water filter fix hard water?

This is where many homeowners get caught.  

A water filter and a water softener do different jobs.

Filtration systems improve water quality by reducing chlorine, sediment and contaminants, while hard water treatment focuses on the calcium and magnesium responsible for scale buildup.

Many homeowners buy and install a whole house filtration system expecting scale to disappear. 

If scale returns, it does not mean the filter has failed. Standard filtration improves water quality, but it does not remove the calcium and magnesium that cause hardness.

Some under sink and whole house filter systems are available with scale reduction filters which change how calcium and magnesium behave in water and help reduce scale buildup, although the minerals do remain in the water.

Reverse osmosis systems also reduce calcium and magnesium and produce soft water, however they typically treat drinking water at a single tap, rather than throughout the home.

For treating hardness across the whole property, a water softener remains the most effective solution. A water softener reduces calcium and magnesium before water reaches taps, appliances and hot water systems throughout the home.

Pairing a whole house filtration system with a water softener is the best way to achieve what we describe as complete home filtration. 

It’s also worth understanding that magnesium is a naturally occurring mineral in water and part of a normal, healthy diet.

Softening reduces calcium and magnesium as part of the process and a remineralising filter can be used as part of a water filtration system to reintroduce beneficial minerals like magnesium.

See why your filter isn’t removing hard water if scale keeps coming back after filtration.

How to treat hard water in WA

Before choosing a solution, start with where the problem shows up.

If the main concern is taste and chlorine at the kitchen tap, an under-sink filter system can address that directly.

If scale is building up across taps, shower screens, tiles, and appliances, a water softener is the right choice.

To tackle both issues, many WA homes choose a whole house filtration system combined with a water softener to achieve true complete home filtration including softer, calcium-free water.

Another popular setup is an under sink filter system paired with a whole house water softener. This improves the quality and taste of drinking and cooking water at the kitchen tap and manages scale across the home.

Our whole house filters and water softeners range shows the systems we install and service. For a closer look at softening, our Perth water softener guide, explains how these systems work and what to expect.

Keeping hard water under control

Installing the right system is only part of the solution. Ongoing maintenance is what keeps it working effectively.

Filters remove chlorine, sediment and other contaminants as water passes through them. Over time, filter cartridges fill up and need replacing. If water filter cartridges are not changed regularly, performance drops and water quality can be affected.

Water softeners also need regular care. Adding salt allows the system to keep reducing calcium and helps prevent scale buildup.

We recommend replacing water filters every 6 to 12 months to protect water quality and maintain system performance. 

In areas like the Pilbara, where sediment and mineral levels are higher, water filter systems work harder, and filters may need to be replaced more frequently.