Evidence, not marketing
Uniwater rates the water technologies people ask us about — what the evidence supports, what is conditional, and what is marketing. We will tell you when something is not worth your money, including things we could sell you.
How we judge it
Does independent, peer-reviewed work support the claim — or only a brochure?
Does it solve a problem your supply actually has — hardness, iron, microbes — not a hypothetical one?
Can the effect be measured at the tap? If it cannot be tested, it cannot be trusted.
Is it safe to live with every day, for years, at the doses involved?
The verdicts
The global standard for drinking water where TDS is high. We size it to your measured TDS rather than overselling it — over-purified water on low-TDS supply is its own problem, which is why we survey first.
What it does — Pushes water through a semi-permeable membrane, leaving dissolved salts, heavy metals, and microbes behind.
Strong evidence · Thousands of peer-reviewed papers; extensive clinical and field validation.
See how we engineer itThe correct, proven answer to hard water. The variable is engineering, not principle — resin grade, vessel sizing, and regeneration design decide whether it lasts. This runs inside HomeSoft and BathSoft.
What it does — Swaps calcium and magnesium ions for sodium across a resin bed, removing the hardness that scales geysers and stiffens skin, hair, and laundry.
Strong evidence · Hundreds of papers; decades of industrial and domestic use.
See how we engineer itThe right treatment for the yellow-stain, orange-marble problem that dominates much of eastern India. Order matters: oxidation and iron removal must come before softening, or the resin fouls. This is core Uniwater engineering.
What it does — Aerates or oxidises dissolved iron and manganese so they precipitate, then filters them out through catalytic media before the water reaches your taps.
Strong evidence · Well-established water-engineering literature and field practice.
See how we engineer itA quiet workhorse. Does exactly one job well and is a sensible stage in most multi-stage systems. Not a standalone answer to hardness or iron.
What it does — Adsorbs chlorine, organic compounds, taste, and odour onto a high-surface-area carbon bed.
Strong evidence · Extensive, long-settled literature.
See how we engineer itEffective for microbiologically unsafe but otherwise low-TDS supply. Needs clear water to work, so it sits after filtration, never instead of it.
What it does — Uses ultraviolet light to inactivate bacteria and viruses without chemicals.
Strong evidence · Strong clinical and public-health evidence base.
See how we engineer itA good fit where the water is low in dissolved salts and the risk is microbial, not chemical. We choose UF over RO when your TDS does not justify demineralising.
What it does — A membrane with pores fine enough to block bacteria and cysts while leaving dissolved minerals in place.
Strong evidence · Established membrane-science literature.
See how we engineer itSound and worth specifying when RO is needed. It restores what aggressive purification strips. Real chemistry, not a marketing cartridge.
What it does — Adds back a controlled amount of calcium and magnesium after RO to correct taste and balance.
Moderate evidence · Moderate but credible literature.
See how we engineer itA real, useful technology for specific chemistries. Note: this is genuine nanofiltration — not 'nano water', which is an unrelated marketing term with no defined meaning.
What it does — A membrane between UF and RO that removes hardness and larger organics while passing some monovalent salts.
Moderate evidence · Solid membrane-engineering evidence.
See how we engineer itGenuinely reduces chlorine for the length of one shower, which can help sensitive skin. But it does nothing for hardness or iron, and the cartridge depletes fast. A comfort add-on, not a water-treatment system.
What it does — Neutralises chlorine at the showerhead using ascorbic acid.
Moderate evidence · Limited but real evidence for chlorine neutralisation.
Early lab work is interesting; durable human evidence is not there yet, and the hydrogen escapes quickly. Worth watching, not worth budgeting for.
What it does — Dissolves molecular hydrogen into water on antioxidant claims.
Weak evidence · Growing but inconclusive human data.
A real cultural practice with a modest antimicrobial basis in small doses. It is not a treatment for hardness, iron, or unsafe supply, and excess copper is its own concern. Keep it as ritual, not infrastructure.
What it does — Stores water in copper for mild antimicrobial effect.
Weak evidence · Small studies; cultural rather than clinical weight.
Quality varies enormously. Proper remineralisation is real; many bolt-on "mineral" cartridges are unverified. Judge the specific product, not the label.
What it does — Inline cartridges claiming to adjust minerals or 'enhance' RO output.
Weak evidence · Sparse independent testing.
No durable change to water chemistry. Independent trials do not reproduce the scale-reduction claims under real flow. We do not install these and would advise against paying for one.
What it does — Clamps a magnet or coil onto the pipe and claims to stop scale without removing hardness.
No credible evidence · No credible supporting evidence.
Too little media, too high a flow rate. They cannot exchange enough hardness ions in the seconds water passes through. For soft water at the shower you treat upstream, at the feed — which is what BathSoft does.
What it does — Showerhead cartridges claiming to soften water on the spot.
No credible evidence · No evidence of meaningful softening at shower flow.
See how we engineer itThe body tightly regulates its own pH; drinking alkaline water does not override it. As a health technology it does not hold up. (Correcting genuinely acidic supply is a separate, legitimate engineering question.)
What it does — Electrically raises water pH on claims of changing body pH.
Weak evidence · Claims unsupported by robust human evidence.
No measurable molecular change, no mechanism, no reproducible benefit. Marketing language, not water treatment.
What it does — Claims to reorganise water into special clusters with health benefits.
No credible evidence · No credible evidence.
There is no defined physics or biology behind the term as marketed. If a seller cannot tell you the mechanism in plain language, that is your answer.
What it does — Uses the word 'quantum' to imply advanced treatment.
No credible evidence · No credible evidence.
Pleasant object, zero effect on water quality. Buy it as decor, not as treatment.
What it does — Suspends gemstones in water for 'energetic' benefit.
No credible evidence · No evidence.
Study volumes shown on each card are indicative and reviewed periodically — a sense of how settled the evidence is, not an exact citation.
From verdict to system
Surveyed first, sized to your water. The verdict above is the easy part — building it to last is the work.
