What is chloramine?
Chloramine is a disinfectant made by adding a small, controlled amount of ammonia to chlorine. Water utilities use it to keep water free of harmful bacteria all the way from the treatment plant to your tap.
Why do water utilities use it?
Plain chlorine fades as water travels through long pipe networks. Chloramine lasts much longer, so it suits big, spread-out cities. It also forms fewer disinfection by-products such as trihalomethanes (THMs). Parts of the Sydney Water and South East Queensland networks use chloramine, and the mix can vary by suburb and season — your utility's water quality page will tell you what's used in your area.
Chlorine vs chloramine
| Chlorine | Chloramine | |
|---|---|---|
| Made from | Chlorine only | Chlorine + a small amount of ammonia |
| How long it lasts in pipes | Fades over shorter distances | Stays active much longer |
| Health guideline (ADWG) | 5 mg/L | 3 mg/L (monochloramine) |
| Goes away if water is left to stand | Partly, over time | Not readily |
| Removed by standard carbon | Yes, quickly | Slowly — needs more contact time |
ADWG = Australian Drinking Water Guidelines (NHMRC). Typical tap water levels are well below these values.
Is chloramine safe to drink?
At the levels used in Australian town water, yes — it's regulated under the Australian Drinking Water Guidelines. Most people who filter it do so for taste, smell and skin comfort in the shower. There are two important exceptions: it must be removed from water for kidney dialysis, and it's toxic to aquarium fish, so fish keepers need a conditioner that neutralises chloramine, not just chlorine.
Can a home filter remove chloramine?
Yes, but it's harder than removing chlorine. Ordinary activated carbon removes chlorine almost instantly, while chloramine needs more carbon and longer contact time. That's why filter size and flow rate matter — a small, fast jug or tap filter may do little, while a larger system with more carbon does much better. Leaving water out or boiling it briefly won't reliably get rid of it.
A common setup: a whole-house filter to improve water at every tap and shower, plus reverse osmosis at the kitchen sink for drinking and cooking water. Reverse osmosis also helps with other concerns such as PFAS — see our guide to Australia's new PFAS limits.
What should I do?
- Check your water utility's website to see whether your area uses chloramine.
- Keep fish? Use a water conditioner rated for chloramine.
- Want better taste and showers? Choose a filter sized for your whole home.
- Change cartridges on schedule — spent carbon stops working.
This guide is general information, not health advice. Source: NHMRC — Australian Drinking Water Guidelines.