Hydration Hub – understanding water, every day
The average human body is around 60% water, yet most of us know little about what we drink each day.
Find answers on what's in your water, how filtration works and what it changes – clearly, and backed by evidence.
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Hydration Hub
Benefits of filtered water: what filtering actually changes
Filtered water is tap water, refined at home: a cartridge reduces chlorine, limescale and certain impurities. The result shows up in three places – the taste in your glass, the scale in your kettle, and the life of your appliances.
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How do Water Filters work? Inside the cartridge, explained
A Water Filter cartridge works with two media in sequence: activated carbon adsorbs chlorine and taste-affecting substances, and ion-exchange resin takes out part of the calcium behind limescale. Here is how each works – and, just as honestly, what a Water Filter can't do.
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How long do water filters last — and when to change yours
Most jug water filter cartridges last about four weeks in everyday use. Here is why the working life is limited, how to change a cartridge properly, and what to do with the old one.
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How water filtration works – in 90 seconds
Ninety seconds on what happens inside a filter cartridge between tap and glass – the mechanism behind much of what you'll read in this hub.
FAQ
What is actually in tap water?
What is actually in tap water?
Tap water is mostly water plus dissolved minerals – mainly calcium, magnesium and trace salts picked up from the rock it passed through. Depending on region and pipework, it can also carry chlorine from treatment, small amounts of metals such as iron or copper, and trace substances modern analysis detects at very low levels. The exact profile varies by region, which is why suppliers publish local water-quality data.
Is tap water safe to drink in the UK?
Is tap water safe to drink in the UK?
Yes – UK tap water is safe to drink and among the most rigorously tested in the world. Suppliers test samples continuously against strict legal standards, and results are published by region. Filtration is not a safety requirement: most people filter for taste, less limescale and better tea and coffee – not because tap water is unsafe.
What does water hardness mean?
What does water hardness mean?
Water hardness describes how much dissolved calcium and magnesium your water carries. Rain collects both as it passes through limestone or chalk, so hardness depends on regional geology. Hard water is safe to drink – the practical effects show up elsewhere: more limescale when water is heated, and a different taste in hot drinks. Your supplier lists the hardness level for your area.
How does a water filter change tap water?
How does a water filter change tap water?
A household water filter changes the composition of tap water – mainly by reducing carbonate hardness and substances that affect taste, such as chlorine. Inside the cartridge, ion exchange swaps out part of the calcium and magnesium, while activated carbon binds taste-affecting substances. The result is not "purer" water in a medical sense; it is water with less scale potential and a cleaner taste.
Why does tap water taste different from place to place?
Why does tap water taste different from place to place?
Tap water tastes different because its mineral profile reflects local geology. Water that passed through chalk or limestone carries more calcium and magnesium and tastes fuller; soft water from granite regions tastes lighter, sometimes flatter. Treatment plays a role too – chlorine levels vary, and older pipework can add its own note. Same standards, different character.
How much water should you drink a day?
How much water should you drink a day?
Most adults need roughly 1.5 to 2 litres of fluid a day – most guidance suggests six to eight glasses. The right amount varies with body size, activity and weather, and food contributes part of it. For healthy adults, thirst is a reasonable guide. All non-alcoholic drinks count towards the total; water is simply the most direct choice.
Does boiling water do the same as filtering it?
Does boiling water do the same as filtering it?
No – boiling and filtering do different jobs. Boiling kills microorganisms but does not remove hardness minerals; as water evaporates, the scale stays behind in your kettle. Filtration with ion exchange reduces carbonate hardness before heating, so less scale forms in the first place. Where tap water is safe, boiling adds little – filtering changes taste and scale, boiling changes neither.
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