The complete guide
Minerals in water, and what they do to how it tastes
Ask people to describe good water and they say "clean", "crisp", or "it tastes of nothing". That last one is wrong, and it is the most interesting thing about water as a drink.
Water with nothing in it tastes bad
Distilled water — H₂O and essentially nothing else — is unpleasant. Most people describe it as flat, hollow, or vaguely metallic. It is not that it tastes of nothing; it is that the absence itself registers as a flavour, and not a good one.
What we recognise as the taste of water is the taste of its dissolved mineral content. Chiefly:
- Calcium — gives body and a faint sweetness; too much reads as chalky.
- Magnesium — adds a slight bitterness that provides definition.
- Bicarbonate — softens and rounds, taking sharp edges off.
- Sodium — in small amounts, enhances everything else, as in food.
- Potassium — subtle, slightly sweet.
This is why bottled mineral waters taste noticeably different from one another despite being, chemically, almost entirely the same substance. The differences sit in the last fraction of a percent.
The subtractive problem
Every filter is subtractive by nature. The question is what it takes out along with the thing you wanted gone.
Carbon filtration is fairly targeted. It adsorbs chlorine and organic compounds and leaves dissolved minerals largely alone, which is why a carbon-filtered glass still tastes like water — better water, but recognisably the same stuff.
Ion exchange deliberately removes calcium and magnesium, which is the point when you are fighting limescale, but it does change the taste. Softened water tastes cleaner and, to some palates, slightly blank.
Reverse osmosis removes almost everything. That is its purpose and its strength, but water straight from an RO membrane has very low mineral content and tastes correspondingly empty. This is exactly why serious RO systems — including the K19-HG in our range — add a remineralisation stage afterwards.
The additive approach
The Santevia takes a different route. It filters with granular activated carbon, targeting chlorine, fluoride and lead, and then routes the water over a mineral stage that adds calcium, magnesium and potassium back before it reaches the tap.
Two things follow from that. The finished water carries mineral content by design rather than by whatever survived filtration, and its pH rises by up to 2 units, which makes it less acidic and, to most palates, softer and rounder.
Whether you like it is a genuine matter of preference. People who find their tap water harsh usually take to it immediately. People who like a crisp, mineral, slightly hard glass of water sometimes find it too smooth.
A note on what we are not claiming
You will find a great deal written about mineralised and alkaline water and health. We are not going to add to it. The mineral content and pH shift here are measurable properties of the product that change how the water tastes, and that is the basis on which we are describing it. Anything beyond that is outside what we can stand behind.
Choosing on taste
If the goal is simply better-tasting tap water, the cheapest carbon filter here does most of the work — the Lucid jug at £24.99 removes the chlorine tang and leaves the minerals. The Santevia is for people who want a fuller intervention: fluoride and lead reduction, a mineral stage, ten litres at a time, and nothing plugged in.