Softener or filter?
Each one fixes a different problem, and in Melbourne one of those problems hardly exists. So the decision is quicker than any sales pitch would suggest.
BlogPublished 31 October 2026By the Eco Purify Water team
In short.
Melbourne's mains water is soft, so a softener has next to nothing to take out. Chlorine, taste and sediment are jobs for a filter.
These are two different machines, and people get sold the wrong one all the time. A water softener deals with hardness, meaning dissolved calcium and magnesium. It trades those ions for sodium in a resin bed, and the resin is regenerated with salt. A water filter takes things out of the water: sediment, chlorine, tastes and smells, and, depending on the type, some metals and chemicals.
Melbourne makes the decision simpler than most cities do, because our mains water is soft. The city's catchments drain protected, forested land without much limestone, so very little calcium and magnesium ends up dissolved in the water. Put a softener on a Melbourne mains supply and it has almost nothing to do.
Just how soft is Melbourne's water?
Soft enough that hard-water advice does not apply here.
Hardness is expressed in milligrams per litre, as calcium carbonate equivalent. To a water chemist, under about 60 is soft, 60 to 120 is moderately hard, 120 to 180 is hard, and anything higher is very hard. The Australian Drinking Water Guidelines treat 200 as the level where scale becomes a nuisance. Most Melbourne suburbs average 8 to 31 from the catchment supply, and it has stayed soft for as long as the retailers have published water quality reports. A few fringe areas, including Whittlesea, Gisborne and Bacchus Marsh, reach 70 to 120. Adelaide has historically been many times harder, and parts of regional Victoria that rely on groundwater or inland rivers are harder still.
In some years, desalinated water from the Wonthaggi plant is blended into Melbourne's supply. It is remineralised before it goes into the network so it does not corrode pipes, and it is still soft. Whichever reservoir your suburb is drawing on this month, your water is unlikely to be the hard water softeners are designed for.
So where does the white film on the kettle come from?
Any water leaves something behind when it evaporates. That is not the scale softeners are made for.
Yes, Melbourne kettles, shower screens and glasses do get a white film. It is usually not the thick calcium scale you see in hard-water cities, though. Soft water still carries some dissolved solids, and whenever water evaporates off a surface, those solids stay behind. Boil a kettle several times a day and they build up. Spots from the dishwasher often come down to rinse aid and detergent, not hardness. On shower screens it is soap scum, which forms when soap meets the small amount of minerals in the water.
A softener would cut this back slightly. In return you get a big tank, ongoing salt, a brine drain, extra sodium in your drinking water, and a few hundred litres a week flushed away regenerating the resin. In most Melbourne homes that is not worth it. A squeegee for the shower screen and a vinegar rinse for the kettle now and then do the same job for free.
The two compared.
What each takes out, what it costs to run, and when it is worth having.
| Whole house carbon filter | Salt-based softener | |
|---|---|---|
| What it takes out | Sediment, chlorine, chloramine, organic compounds, tastes and odours. Carbon block also reduces some metals and cysts. | Only calcium and magnesium, and it puts sodium in their place. |
| What it leaves alone | Hardness, fluoride, salts and dissolved minerals. It does not soften water. | Chlorine, sediment, taste and odour. Softened water still smells of chlorine. |
| Worth it in Melbourne when | The problem is chlorine smell or taste, skin and hair comfort, or sediment in fixtures and appliances. That covers most homes that enquire. | Hardly ever on mains water. Sometimes on bore water at the urban fringe, if a water test finds genuine hardness. |
| Ongoing costs | One cartridge set a year. The Care Plan delivers the set, and on the fitted plan we fit it too. | Salt every few weeks, new resin every several years, the water used to regenerate, and added sodium in your drinking water. |
| Space needed | One cabinet on the wall near the meter. | A resin tank and a brine tank, plus a power point and a drain connection. |
| Pipes and appliances | Stops grit reaching aerators, valves, hot water services and the inlet screens on appliances. | Cuts scale. That counts in hard-water regions, not in Melbourne. |
Conditioners, magnets and other alternatives.
Three things sold in place of softeners, and what the evidence shows.
Scale inhibitors, also sold as conditioners, rely on template-assisted crystallisation or polyphosphate media to stop the little calcium there is from sticking to surfaces. They need no salt and no drain. They also do nothing for chlorine or sediment, and in soft water they have very little work to do.
Magnetic and electronic descalers clip onto a pipe and claim their field changes the minerals. Independent testing has failed, again and again, to find a reliable effect. In Melbourne, they use a method that does not work on a problem the water does not have.
On bore water or a rural supply and worried about hardness? Have the water tested by a NATA-accredited laboratory before you spend anything. Once hardness goes above about 120 milligrams per litre, a softener starts to pay its way. Under that, it seldom does.
What we sell and what we do not.
A single system, and an honest answer when it is not the right fit.
Eco Purify Water sells one thing: a three-stage carbon filtration system for the whole house. Softeners are not on our list, because Melbourne homes on mains water do not need one, and we would sooner tell you so than take your money. If someone quotes you a softener for a Melbourne mains supply, ask what hardness figure the quote is based on.
- Chlorine taste, smell or odour: carbon filtration sorts it out.
- Grit in appliances or aerators: a sediment stage sorts it out.
- Heavy scale in a Melbourne home on mains water: get the water tested before you accept that diagnosis.
Common questions.
Plain answers you can use.
Is Melbourne's water soft or hard?
Soft. Water from Melbourne's protected catchments carries very little dissolved calcium and magnesium, with most suburbs averaging 8 to 31 milligrams per litre as calcium carbonate. Parts of the fringe, like Whittlesea, Gisborne and Bacchus Marsh, sit at 70 to 120: moderately hard, but still short of the point where a softener earns its keep. See the figures by area.
Does a Melbourne home need a water softener?
If you are on mains water, almost certainly not. Softeners remove hardness, and Melbourne's water has very little of it. On bore water at the fringe, test first. A result above about 120 milligrams per litre is when a softener is worth a look.
How is a water filter different from a water softener?
A softener exchanges calcium and magnesium for sodium so scale does not form. A filter takes out sediment, chlorine, tastes, odours and some chemicals. Softeners leave chlorine in, and filters do not soften.
If the water is soft, why does my kettle get a white film?
All water has some dissolved solids, soft water included, and boiling concentrates them. What you see is a light deposit, not the hard scale found in hard-water cities. A rinse with vinegar takes it off.
Does a whole house filter prevent scale?
No. Carbon does not take out hardness minerals, so scale is neither better nor worse. In Melbourne that seldom matters, as there is so little hardness in the first place. The filter is there for chlorine, taste, odour and sediment.
Keep exploring.
What a filter will fix, and the price.
Chlorine in your shower water
Why a Melbourne shower smells of chlorine, its effect on skin and hair, a shower filter compared with whole-home carbon filtration, and what carbon cannot remove, fluoride included.
How a whole-home water filter works
The three stages and what each one takes out, where the system goes on your property, and what to expect on installation day.
What a whole house water filter costs in Melbourne
Our fixed installed price and each item it covers, market ranges for supply-only and installed systems, what a plumber charges on top, Care Plan cost per year against buying cartridges yourself, and what moves the price (meter location, pipe size, access).
Common questions
Cartridge life, water pressure, installation, tank water, fluoride, pricing and the Care Plan.
Has someone quoted you a softener?
Send the quote through with your suburb. We will tell you if your water is hard enough to need one, and we do not sell softeners, so we gain nothing either way.