Chlorine, chloramine and vitamin C shower filtration
Chloramine does not evaporate. That is the whole problem, and it decides what a filter has to do.
What is the difference between chlorine and chloramine?
Water utilities choose disinfectants for supply-network needs. The type used locally affects which shower-filter media are relevant.
Free chlorine. Some of it leaves on the way down.
Free chlorine is more volatile
Free chlorine can move from water into the air, which can make its smell more noticeable in a hot shower.
Where you will meet it: Melbourne, Brisbane and Ipswich, metro Perth, and most of Adelaide.
Chloramine. Same recess, same spray, nothing leaving.
Chloramine is more stable in water
Chloramine combines chlorine with ammonia. Utilities use it because it maintains a disinfectant residual across longer supply networks.
Where you will meet it: Sydney, and the long pipelines feeding parts of South Australia.
Check whether your water uses chlorine or chloramine
Sydney Water classes anything below 60 mg/L as soft. Under that line, limescale is not your problem.
| City | Hardness | Class | Disinfectant | Source |
|---|---|---|---|---|
| Sydney | about 57 | Soft | Chlorine with ammonia added, so chloramine | Sydney Water |
| Melbourne | 18, range 15 to 27 | Very soft | Free chlorine, about 0.76 mg/L residual | South East Water |
| Brisbane and Ipswich | about 100 | Moderately hard | Free chlorine, about 2 mg/L. Not a chloramine city | Urban Utilities |
| Perth | 29 to 228 by suburb | Soft to hard | Chlorine in the metro area. Chloramine in the Goldfields, not metro Perth | Water Corporation |
| Adelaide | about 97 | Moderately hard | Mixed. Chlorine across the metro area, chloramine on the long pipelines | SA Water |
| Canberra | about 43 | Soft | Not confirmed | Icon Water |
| Hobart | Not obtained | Unknown | Not obtained | Published figures only |
Sources as listed: South East Water's Drinking Water Quality Report 2024 to 2025, Urban Utilities' 2023 to 2024. Figures are city-level averages and your suburb can sit well away from them, which is the entire point of the Perth row.
Adsorption and chemical reduction work differently
Understanding the mechanism helps you compare media for free chlorine and chloramine.
Left, adsorption. Held on a surface until the surface runs out of room. Right, chemical reduction. Converted, and the acid is used up doing it.
A Vita cartridge in section. The media is consumed rather than filled.
Adsorption
Activated carbon adsorbs compounds onto its internal surface area.
It is physical rather than chemical, and the carbon fills up. That is why carbon cartridges are rated in litres.
Carbon is widely used for free chlorine. Chloramine treatment depends on the carbon type, product design and available contact time.
Chemical reduction
Ascorbic acid, which is vitamin C, acts as a reducing agent and reacts with chlorine compounds.
This is a chemical reaction rather than adsorption onto a surface.
The ascorbic acid is consumed through use, which is why the cartridge requires replacement.
That is the media in Vitae Infusion.
What the published evidence does and does not show
Compare the reaction mechanism, contact time, flow data and certification scope before assessing a vitamin C shower filter.
Contact time
Water passes through a showerhead in a fraction of a second. A bench test in a beaker gives the reaction close to a minute.
Contact time depends on the installed flow rate and cartridge design. Radiance and Nourish recorded a mean flow rate of 5.0 L/min in the cited SLS test.
Both handshowers were measured at 5.0 litres a minute by Singapore Laboratory Services.
A lower flow rate can increase contact time within the same cartridge geometry. See the Aera Flow measurements and test scope.
Singapore Laboratory Services, report 22608188-CLC, 19 March 2026. 5.0 litres a minute, tested to AS/NZS 3662:2013.
The argument in full, and the test conditions
The objection runs like this. Manufacturer bench tests are often run in a beaker, where the water and the vitamin C sit together for close to a minute. A reaction which finishes comfortably in a beaker has not, on that evidence, been shown to finish in a showerhead. It is a fair argument and it is the best one anyone makes.
The flow figure is the mean across 1.5, 2.5, 3.5, 4.5 and 5.0 bar, measured under clause 5.1 and appendix B of the standard, and it sits in the top efficiency band of 5 litres a minute or less. The laboratory is SAC-SINGLAS accredited.
The report covers the Radiance handshower in chrome and black and the Nourish handshower in chrome. The plate is a patented design with triangular openings around 0.3 mm across, up to ten times smaller than a conventional shower hole, which is how it holds the spray up on less water.
Certification scope
NSF/ANSI 177 covers free chlorine, not chloramine. Check the certifier’s public database for the exact product model.
What holding it would and would not tell you
A small number of specialist water treatment systems hold it. Certification means an independent body has tested the product against a written protocol and continues to audit it, which is more than an in-house test.
It certifies free chlorine reduction. If you live somewhere chloraminated, a 177 certificate is real, and it is not answering the question you are actually asking.
Who makes these arguments, and why
Both are published by companies that sell a different filter media, so they have a commercial reason to make them. That does not make them wrong.
Why we published it anyway
Flow rate physics and the arithmetic of how much reactant a reaction needs do not care who is doing the arguing.
What the water utility says
South East Water says on its own website that you do not need to filter your water. They are right, and it is worth knowing they are right.
The residual is there on purpose, and that is the question a utility is asked. Whether it is pleasant to stand under for ten minutes a day is a different question.
Common questions
Does my city use chlorine or chloramine?
Depends where you are. Sydney is chloraminated. Melbourne, Brisbane and metro Perth use free chlorine. Adelaide runs a mix, with chloramine on the long pipelines. The table above has the sources. If you want it at suburb level, the water lookup is more precise than a city average.
Does chloramine evaporate out of the water like chlorine does?
No, and that is the point of using it. Chloramine is more stable than free chlorine, which is why utilities pick it for long networks. It is still in the water when the water reaches you.
Is vitamin C better than carbon?
Vitamin C and carbon work differently. Vitamin C uses chemical reduction, while carbon relies on adsorption. Compare evidence for the exact medium, product design and test conditions.
Is Suhae certified to NSF/ANSI 177?
No. SUHAE is not certified to NSF/ANSI 177. Check every certification claim against the exact product model, standard and certifying body.
Do I have hard water?
If you live in Sydney, Melbourne or Canberra, almost certainly not. Sydney Water classes anything under 60 mg/L as soft, and all three sit below it. Brisbane and Adelaide are moderately hard. Perth genuinely depends on the suburb.
So should I buy a shower filter?
Use our Australian shower-filter buyer’s guide to compare media, evidence, fit and running cost.
Start with your own water
Check which disinfectant your utility uses, then compare filtration media, evidence and fitting compatibility.
City and utility data on this page links to the named source.