Chloramine and PFAS in Australian Water

Two of the trickiest things to get out of Australian tap water. They need specific filtration — a basic carbon filter will not cut it. If you are on Sydney, Melbourne, Brisbane, Adelaide, or Canberra mains water, you almost certainly have chloramine. If you live near a defence base, airport, or industrial site, PFAS may be a concern too. Different problems, different solutions, both fixable.

What is chloramine?

Chloramine is chlorine combined with ammonia, used as a mains water disinfectant. Water authorities switched to it because it stays stable longer in big-city pipe networks than chlorine does. The trade-off: it is much harder to filter out.

Standard granular activated carbon (GAC) — the cheap stuff in most under-sink filters — does not remove chloramine reliably at normal household flow rates. The water moves through the cartridge too fast for the chemistry to work. You need catalytic carbon, a specifically processed form of activated carbon with the surface structure needed to break chloramine down.

The other reason chloramine matters is your shower. Hot water releases chloramine as vapour, which you breathe in and absorb through your skin. For people with eczema, asthma, or sensitive skin, this is often a bigger exposure than drinking water. Boiling does not remove it.

Does your supply use chloramine?

In Australia, chloramine is used by Sydney Water, Melbourne Water, SA Water (Adelaide), Urban Utilities (Brisbane), and Icon Water (Canberra), among others. Smaller regional supplies vary. The fastest way to find out is to search your water authority's most recent annual water quality report for "chloramine" or "monochloramine".

What removes chloramine

For drinking water only, a catalytic carbon cartridge in an under-sink filter is enough. Cheap and simple.

For the shower and the rest of the house, you need a whole-house system with catalytic carbon in at least one stage. Big Blue 20" × 4.5" housings are the right size — they give the cartridge the contact time it needs at whole-house flow rates. Smaller standard housings flush water through too fast.

A three-stage Big Blue setup typically runs: sediment pre-filter → catalytic carbon → carbon block polish. Browse the whole-house category for systems in this configuration.

What is PFAS?

PFAS — per- and poly-fluoroalkyl substances — are a family of synthetic chemicals used in firefighting foam, non-stick coatings, water-resistant clothing, and food packaging. They are called "forever chemicals" because they do not break down naturally.

In Australia, PFAS contamination has been documented in groundwater and some drinking water supplies near defence bases (where firefighting foam was used), airports, and certain industrial and agricultural sites. The Australian Government runs a PFAS investigation portal covering known sites. Your state environment authority will have local maps.

If you are on town water far from any of these areas, PFAS is unlikely to be your problem. If you are on bore water near a known contamination zone, get a water test before deciding on filtration.

What removes PFAS

At point of entry (whole-house), high-quality activated carbon — particularly carbon block — reduces longer-chain PFAS (PFOS, PFOA) substantially. PFAS-specific ion-exchange resins cover the shorter-chain variants that carbon misses.

At point of use (kitchen tap), reverse osmosis is the most thorough option. RO is impractical at whole-house scale due to flow and waste-water issues, but as a final stage on drinking water it removes virtually everything.

For most households with PFAS concerns, the right setup is: a whole-house carbon-block stage for general use, plus an RO system at the kitchen tap for drinking water.