One system.Filtered water with limescale protection.

The final stage uses a compressed carbon block: a denser, finer form of activated carbon that catches anything the upstream stages may have missed. Its extremely small particle size (50–325 mesh) gives superior contact with the water and more thorough removal of residual chlorine, taste compounds, and odour.

This is the stage that makes the difference you notice immediately. Tea and coffee taste cleaner. The swimming-pool smell disappears from your shower. Cooking water is genuinely pure.

Carbon block filtration is the technology behind NSF/ANSI Standard 42, the internationally recognised benchmark for drinking water aesthetic quality. The same core technology used in premium under-sink systems, applied here to your entire home.

Activated carbon is one of the most extensively studied water treatment media in the world. It works through adsorption: contaminants bind to the vast internal surface area of the carbon granules as water passes through. A single gram of quality activated carbon has a surface area of roughly 3,000 m², about the size of half a football pitch.

This makes it exceptionally effective at trapping dissolved organic chemicals including pesticides, herbicides, volatile organic compounds (VOCs), and pharmaceutical residues.

Critically, GAC is now recognised by the U.S. EPA as one of the Best Available Technologies for removing PFAS ("forever chemicals") from drinking water, a growing concern in municipal supplies across the UK and Europe.

KDF-55 media is a high-purity alloy of copper and zinc granules. When water passes through, a natural electrochemical (redox) reaction occurs: electrons transfer between the metals and dissolved contaminants, converting harmful heavy metals into inert forms that bond to the media surface.

This is particularly relevant for older UK properties where lead service pipes and copper plumbing can leach metals into drinking water. KDF also creates conditions that inhibit the growth of bacteria, algae, and fungi within the filter, keeping the downstream stages cleaner for longer.

As a secondary benefit, KDF handles chlorine and metals upstream, freeing the GAC in Stage 2 to focus on organic compounds and PFAS, extending its working life significantly.

Hard water leaves limescale inside boilers, hot water systems and appliances. It costs a hard-water home £400-600 a year in wasted energy, repairs and early replacements.

ScaleStar™ uses Nucleation Assisted Crystallisation (NAC). Dissolved calcium and magnesium crystallise on microscopic sites in the media, then detach as stable crystals that stay suspended in the water and flow through instead of building up. The minerals stay in; more than 88% less hard scale forms. No salt, no sodium, no waste water, no electricity. Media replaced every 24 months.

What to expect. Your boiler, hot water system and appliances are protected from hard scale build-up. On glass, around taps and in the kettle you may still see a fine chalky film where water dries. It wipes off with a cloth rather than a descaler. Existing scale needs one last clean after install. Your water will still test as hard, because the minerals are still in it.

The evidence. The type of salt-free media in ScaleStar™ was independently tested by Arizona State University for the WateReuse Research Foundation, using the German DVGW W512 protocol, which measures scale forming on a water heater element. It cut scale by more than 88%, the best of the salt-free technologies tested. Separate testing by Battelle shows what that scale costs: gas water heaters on very hard water fell from 80% to 72% efficiency within 1.6 years of use. W512 requires 80% to pass; the US standard, IAPMO/ANSI Z601, requires 70%. Housings are WRAS-approved for UK mains use.