The comparison
Every common way of treating water, side by side.
Fifteen categories of contaminant, ten arrangements, and what each one costs you in minerals, in water sent to the drain, in electricity and in money. This is the long version. If you only want to know which filter we recommend and how to use it, that is on the filtration page.
Coverage
Every common setup, with and without Aurmina
Fifteen categories of contaminant, grouped by how they behave in a filter rather than by how they are regulated. Find your setup and read across. The number is what matters — it is the count of categories still present.
The fifteen categories
- SEDSediment, turbidity, rust, silt
- METDissolved heavy metals — lead, mercury, arsenic, cadmium, uranium
- BACBacteria and protozoan cysts (Giardia, Cryptosporidium)
- FLUFluoride
- VIRViruses
- NITNitrate and nitrite
- MPMicroplastics, 1 µm and larger
- CLChlorine, chloramine, taste and odour
- NPNanoplastics, below 1 µm
- DBPDisinfection byproducts — THMs, haloacetic acids
- ORGOrganic chemicals — solvents, VOCs, pesticides, herbicides
- PFA-LLong-chain PFAS, C6 and above, including PFOA and PFOS
- PHMPharmaceuticals
- HRMHormones — natural and synthetic estrogens, androgens, progestins
- PFA-SShort-chain PFAS, C4–C5 — PFBA, PFPeA
| Filter typeand common brand names | Without pre-treatmentcategories not removed | Pre-treated with Aurminacategories still not removed |
|---|---|---|
| No filter, or a paper coffee filterNo plumbingTreat in a jar, let it stand, then pour the clear water off the top — or run it through a coffee filter | SEDMETBACFLUVIRNITMPCLNPDBPORGPFA-LPHMHRMPFA-SAll 15 present Untreated tap water, straight from the tap |
BACVIRNPNITPFA-LPFA-SHRM*7 present8 removed Both land in the same place. The coffee filter is the better of the two only because it captures the floc reliably, which decanting cannot promise. + WATER CHEMISTRY |
| Granular carbon + ion exchangeNo plumbingBrita Standard and Elite · PUR · most pitchers and faucet mounts | BACVIRNPFLUNITPFA-SPFA-L‡6–7 present | BACVIRNPNITPFA-S5 present2 removed + WATER CHEMISTRY |
| Zero-TDS ion exchangeNo plumbingZeroWater · Culligan ZeroWater pitchers and dispensers | BACVIRNPDBPORGHRMMET◊7 present The most capable pitcher here — certified for fluoride, nitrate, PFAS and most metals. It also strips every mineral, by design. |
BACVIRNPDBPORGHRMMET◊7 present Dose after, not before. Pre-treating works on the contaminants, but the resin then strips every mineral Aurmina adds, the redox activity and ion-exchange capacity with them. Add it to the filtered water instead, as with reverse osmosis. + WATER CHEMISTRY |
| Ceramic element aloneNo plumbingDoulton Super Sterasyl · British Berkefeld · the Korea Ceramics dome we sell | VIRNPCLDBPORGPHMHRMMETFLUNITPFA-LPFA-S12 present | VIRNPNITPFA-LPFA-SHRM*6 present6 removed + WATER CHEMISTRY |
| Carbon block alonePlumbed inAquasana · Clearly Filtered · Hydroviv · most under-sink cartridges | BACVIRNPMETFLUNITPFA-S7 present | BACVIRNPNITPFA-S5 present2 removed + WATER CHEMISTRY |
| Composite carbon + ion-exchange blockNo plumbingBlack Berkey elements and similar gravity blocks | NPFLU§NITPFA-S4 present | NPNITPFA-S3 present1 removed + WATER CHEMISTRY |
| Ceramic or membrane + carbon in seriesNo plumbingDoulton UltraCarb candle · British Berkefeld Ultra Sterasyl · LifeStraw Home pitcher | VIRNPMETFLUNITPFA-S6 present | VIRNPNITPFA-S4 present2 removed + WATER CHEMISTRY |
| Ceramic + carbon + ion exchangeNo plumbingOur dome above the stock five-stage cartridge in a Zenwater, Nispira or Korean gravity housing | VIRNPFLUNITPFA-S5 present | VIRNPNITPFA-S4 present1 removed Mineral profile: the stock cartridge holds an ion-exchange resin that swaps calcium and magnesium for sodium. It will take back some of the mineral character Aurmina left in. + WATER CHEMISTRY |
| Ultrafiltration + carbonPlumbed inFrizzlife GX99 · Waterdrop TSA-UF and TSU-W · hollow fibre at 0.01–0.02 µm | METFLUNITPFA-S4 present | NITPFA-S2 present2 removed + WATER CHEMISTRY |
| Reverse osmosis / distillationPlumbed in or countertopiSpring · APEC · AquaTru · countertop distillers | None present Demineralised. Nothing left to remove — and nothing left in. No mineral content, no redox activity, no ion-exchange capacity. |
None present Aurmina’s broad inventory of trace elements, all at minute concentrations, is what you are drinking here — and with it the redox activity, ion-exchange capacity and hydration-shell chemistry the membrane took out. The calcium and magnesium do not come back. Dose after treatment, never before. + WATER CHEMISTRY |
| RO + remineralisation cartridgePlumbed inA short list of minerals added back downstream | None present Demineralised, then a short list of minerals added back downstream. The redox activity and ion-exchange capacity do not come back with them. |
None present Aurmina’s broad inventory of trace elements, all at minute concentrations, plus the redox activity, ion-exchange capacity and hydration-shell chemistry it carries — and on top of that the short list of calcium and magnesium the cartridge puts back, at concentrations that count. + WATER CHEMISTRY |
+ WATER CHEMISTRY
appears on every treated row because the count is only half of what Aurmina does. The treatment leaves a broad inventory of trace elements behind, and with them redox activity, ion-exchange capacity, and stronger hydration shells — the last because the solution is sulfate-dominant and magnesium-rich, and sulfate and magnesium sit at the kosmotropic end of the Hofmeister series, where ions hold water most tightly. None of that is a contaminant category, so none of it is in the numbers. It is the second reason to do this.
What the table adds up to
Read down the two right-hand columns and one pattern holds all the way. On every arrangement on this page, treating the water first leaves fewer categories present than filtering alone — while also restoring the water’s chemistry. Fifteen becomes seven. Twelve becomes six. Seven becomes five. Six becomes four. Four becomes two. And every one of those rows carries + WATER CHEMISTRY as well.
Reverse osmosis, distillation and the zero-TDS pitchers are the exceptions, and for two different reasons. On reverse osmosis and distillation there is nothing left to subtract — it already clears every category on its own. What Aurmina adds there sits on the other side of the ledger: the broad inventory of trace elements the membrane took out, and with them the redox activity and ion-exchange capacity that mineral-bearing water carries.
So the honest summary is not that Aurmina replaces your filter, or that you should buy a different one. It is that on the published capabilities of these methods and our own treatment data, pre-treatment should broaden what the combination removes. That is the whole claim. Most of these combined arrangements have never been tested end to end as complete systems — ours included — so read the table as what the mechanisms predict, not as measured results.
The trade
What each setup costs you.
Same rows, same order. Coverage is only half the decision — the other half is what you give up to get it. No configuration wins on all four, and we do not sell most of what is listed here.
| Filter typeand example products | Minerals | Water wasted | Power | Cost |
|---|---|---|---|---|
| No filter, or a paper coffee filterNo plumbingA second jar, or a cone and a box of filters | Kept | None | None | Nothing, or a few cents a batchCoffee filters are single use and blind quickly on floc |
| Granular carbon + ion exchangeNo plumbingBrita Standard · Brita Elite · PUR | KeptThe resin targets cadmium, copper and zinc, not hardness — Brita makes no softening claim | None | None | Pitcher $25–40Brita Standard rated 40 gal — about two months |
| Zero-TDS ion exchangeNo plumbingZeroWater · Culligan ZeroWater | Stripped99.6–99.9% of total dissolved solids, which is the product’s entire premise | None | None | $44–77 a yearPitcher $25–50. Filters run about $11–18 and exhaust by TDS rather than time — 40 gallons on soft water, under 8 on hard. Most households change 4 to 7 a year |
| Ceramic element aloneNo plumbingDoulton Super Sterasyl · our Korea Ceramics dome | Kept | None | Gravity | Element $10–501–2 years, washable in between. Housing cost depends on the vessel — the ones we know take this dome are the three listed at the top of the page |
| Carbon block alonePlumbed inAquasana AQ-5200 · Clearly Filtered · Hydroviv | Kept | None | None | $100–200 installedCartridges every 6–12 months |
| Composite carbon + IX blockNo plumbingBig Berkey, two Black Berkey elements | KeptBerkey states the element is not designed to remove ionic minerals — their claim, not third-party tested | None | Gravity | About $384 ¶Elements 6,000 gal a pair · fluoride needs the PF-2 |
| Ceramic or membrane + carbon in seriesNo plumbingBritish Berkefeld Ultra Sterasyl, $67 · Doulton UltraCarb, ~$90 · LifeStraw Home pitcher, $44.95 | Kept | None | Gravity | From $45Carbon is the recurring item — six to twelve months |
| Ceramic + carbon + ion exchangeNo plumbingZenwater · Nispira · Korean gravity housings, with our dome above the stock cartridge | Partly — the resin swaps calcium and magnesium for sodium | None | Gravity | Housing $123–208Five-stage cartridge replaced every 6–12 months |
| Ultrafiltration + carbonPlumbed inFrizzlife GX99 · Waterdrop TSA-UF · Waterdrop TSU-W | KeptIons pass a 20 nm pore freely | Little to none | Line pressure | $112–140Must be plumbed in |
| Reverse osmosis / distillationPlumbed in or countertopiSpring · APEC · AquaTru · countertop distillers | Stripped | 3–9 glasses wasted per glass filteredA distiller wastes almost none — only the residue left in the boiler | Pump on mostTankless and countertop units all run one. A classic tank system needs no electricity at all — it works on line pressure. A distiller boils every glass, roughly 4 kWh per gallon | $300–585 a yearOn top of the system itself. A distiller runs about $250 a year in electricity at a gallon a day |
| RO + remineralisationPlumbed inA short list of minerals added back | A few, at low levels | 3–9 glasses wasted per glass filtered | Pump on mostNone on a classic tank system, which runs on line pressure | $300–585 a yearPlus the cartridge |
Prices checked September 2026 and offered as guidance only — they move, and retailers differ. We sell one item on this list, the ceramic element, and earn nothing from any of the others. ¶ Berkey systems have been supply-constrained; check availability before planning around one.
If you asked us what we would run
Treat in a separate vessel, let it stand, then pass the clear water through a ceramic element followed by a carbon stage. Three mechanisms in the path — coagulation, size exclusion, adsorption — four categories still present, minerals intact, no electricity, nothing down the drain.
Be honest with yourself about whether you need the carbon, though. Once the water has been treated, the benefit of adding a carbon stage comes down to two things: long-chain PFAS and hormones. Everything else people buy carbon for — chlorine, disinfection byproducts, organics, pharmaceuticals, metals, fluoride — the treatment has already removed. If either of those is a concern on your supply, get the carbon. If not, run the dome and keep your money.
Reverse osmosis beats all of it on contaminants and we are not going to pretend otherwise. It clears every category in the legend. What you pay for it is the absence of all mineral content, three to nine glasses down the drain for every glass you drink, the electricity on most systems, and three to six hundred dollars a year. That is a real trade, and on some supplies it is the right one.
Ultrafiltration paired with carbon is the arrangement we are most curious about and have least data on. On mechanism it should leave only two categories present once the water is treated — the tightest residual on this page without demineralising. It has to be plumbed in under the sink, and it costs about a hundred and thirty dollars. We have not tested it. When we do, it goes on this page whichever way it falls.
How to read these tables. Each row describes what that arrangement is built to do, drawn from the manufacturers’ own published specifications. We have not tested these systems ourselves, with or without Aurmina.
SED and MP appear only in the first row, because every actual filter on this table removes both — sediment and microplastics are the easiest things in water to catch.
On the gravity housings. We list the Zenwater, Nispira and Korean systems as vessels that accept a standard ceramic dome, nothing more. We have not tested them, we earn nothing from them, and this is not an endorsement of the filters they ship with. One thing worth knowing before you decide: the stock five-stage cartridge contains an ion-exchange resin that removes some calcium and magnesium. The activated carbon in that cartridge is doing real work. The rest of the stack is marketed on claims we address further down this page.
A word on minerals, and on ion exchange. Not all ion exchange is the same, which is why only one row above carries a mineral warning. The resins in most pitchers and composite blocks are built to catch cadmium, copper, zinc and lead and leave hardness alone. A softening resin is a different thing — it swaps calcium and magnesium for sodium — and among the systems here only the stock five-stage cartridge contains one. Every row except reverse osmosis and distillation keeps the calcium and magnesium the water arrived with, and adds Aurmina's broad inventory of trace elements on top. Reverse osmosis and distillation are the exception: they strip the source minerals, so what you drink afterwards is whatever Aurmina and any remineralisation cartridge put back, and nothing else.
Microbiological categories. Neither decanting nor a coffee filter puts any microbiological barrier in the path. On chlorinated municipal water that is usually of no consequence — US surveillance recorded 214 drinking-water outbreaks nationally across six years, 87% of them Legionella growing in building plumbing rather than anything arriving from the treatment plant. On private wells it matters a great deal: those serve 13% of the population, are not covered by the Safe Drinking Water Act, and accounted for 44% of outbreak cases. Use a rated element on any untreated source.
* HRM is the one category on this table that is reduced rather than removed. Aurmina ahead of a ceramic element cuts hormone concentrations substantially — more so for estrogens than for androgens — but not to zero. A carbon stage adsorbs what remains, which is why every row that includes carbon clears it. The laboratory data is published separately.
◊ ZeroWater is certified for lead, mercury, cadmium, copper and hexavalent chromium, but not for arsenic or uranium, so the metals category is only partly covered. It is also uncertified for chloramine and VOCs. † Manufacturer claim, not third-party certified. § Requires the separate PF-2 fluoride and arsenic add-on. ‡ Long-chain PFAS reduction varies widely between pitcher models — check the model's certification, not the brand.
On PFAS and carbon. The EPA lists granular activated carbon as one of four best available technologies for PFAS, alongside anion exchange, reverse osmosis and nanofiltration. Column testing shows it works well from C6 upward and poorly below — roughly 23,000 bed volumes to breakthrough for PFOA against 6,000 for PFBA. On a loaded bed, competing contaminants can displace PFAS already adsorbed, so unlike taste and odour, PFAS performance does not fade gracefully at end of life.