ScaleSoft® Triple Whole House Chloramine & Hard Water Filter System | 20" x 4.5" High Flow | WaterMark (GT1-SS-20B-CRC)

Triple Whole House Chloramine & Hard Water Filter System | 20" x 4.5"

A three-stage whole house system for mains water treated with chloramine. It fits a GT4-19CRC catalytic carbon block, a 20" x 4.5" sediment filter and a ScaleSoft® SS-20B scale-control cartridge, pre-assembled on a stainless steel bracket with pressure gauges fitted.

The catalytic block is what separates this model from the rest of the range. Standard carbon does not reduce chloramine.

Which model you need

Chloramine is chlorine combined with ammonia. Operators use it where the disinfectant has to hold through a long run of pipe. It is chosen by the network operator, not by state or council, so two houses in one city can be on different supplies.

Red is where the network operator uses chloramine, including networks where only part of the system does. Purple means the operator does not publish which disinfectant it uses, the area sits on a changeover boundary, or the supply uses neither. It does not mean the water is untreated. Grey is not assessed. Classification is by local government area, so a boundary on the map is a council boundary, not a pipe.

Area	Network operator	Usually disinfected with	Model
Sydney	Sydney Water	Chloramine	CRC
South East Queensland, excluding the southern Gold Coast	Urban Utilities, Unitywater, Logan Water and City of Gold Coast, on Seqwater bulk supply	Chloramine	CRC
South Australia, the whole state	SA Water	Chloramine in a large part of the network	CRC
Southern Gold Coast	City of Gold Coast, on Seqwater bulk supply	Free chlorine	LRC
The Wheatbelt and Goldfields, on the Goldfields and Agricultural Water Supply Scheme (27 shires)	Water Corporation	Chloramine	CRC
Perth metropolitan	Water Corporation	Free chlorine	LRC
Ballarat, Bendigo and the central Victorian goldfields	Central Highlands Water, Coliban Water and Barwon Water	Chloramine	CRC
Melbourne	Yarra Valley Water, South East Water and Greater Western Water	Free chlorine	LRC
Canberra	Icon Water	Free chlorine	LRC
Hobart and the rest of Tasmania	TasWater	Free chlorine	LRC
Darwin and the rest of the Northern Territory	Power and Water Corporation	Free chlorine	LRC
Anywhere not listed above	Confirm with your network operator	Not confirmed	CRC

CRC is this system, GT1-SS-20B-CRC. LRC is GT1-SS-20B-LRC, which fits a lead and heavy metal reduction block instead.

Operators change practice. Check your provider's water quality report if you want to be certain. If you are not sure, order the CRC. The catalytic block reduces free chlorine as well, so it suits either supply.

Why chloramine needs catalytic carbon

Standard activated carbon reduces free chlorine through a surface reaction. Chloramine does not undergo that reaction at the contact times a household filter gives it, so standard carbon does not treat it. Catalytic carbon decomposes the chloramine molecule instead.

Chloramine gives no warning. Free chlorine you can smell and taste, so you know when a carbon block is spent. Chloramine you cannot. A system with the wrong carbon on a chloraminated supply still handles the sediment and the scale, and leaves the chloramine in the water.

GT4-19CRC is the only catalytic block made in 20" x 4.5". That is why this model fits one carbon and does not offer a choice of block.

Supply pressure: 350 kPa to 500 kPa

The catalytic block is 0.5 micron and needs pressure behind it to run at rated flow. Check your supply before ordering.

There is no lower-pressure catalytic block in this size, so this is a requirement rather than a preference. If your pressure is under 350 kPa, or you have not measured it, call us before you order. We sell a pressure test kit if you need one.

What is the issue with hard water?

• It builds up inside kettles, dishwashers and coffee machines, and shortens their working life.
• It coats the elements in hot water systems and the inside of your pipework.
• It leaves spotting and film on taps, shower screens and glassware.

How hard your water is depends on where your supply comes from. Hardness varies widely between regions.

How the scale-control stage works

Step 1. Water enters the cartridge. Hard water carries scale-forming calcium and magnesium, which are attracted to the ScaleSoft® media.

Step 2. The media converts those minerals into microscopic, stable crystals. Once the crystals become too large, they detach from the media.

Step 3. The crystals stay suspended and flow through with the water, instead of bonding to your pipes and elements.

Worth knowing. ScaleSoft® conditions hardness rather than removing it. It is a scale-control cartridge, not an ion exchange softener, which is why it needs no salt, no power and no drain.

Where each cartridge sits

The order is sediment, then catalytic carbon, then ScaleSoft®. Chloramine, taste and odour are dealt with before the water reaches the scale-control media, which helps that cartridge run its full service life.

Housing	Cartridge	Part code
Stage 1	Sediment, 5 micron polyspun	GT2-28K
Stage 2	Catalytic Carbon, 0.5 micron catalytic coconut carbon block	GT4-19CRC
Stage 3	ScaleSoft®, salt-free scale control	SS-20B

Why people choose this system

• Chloramine treated properly. A catalytic block that decomposes it, which a standard carbon does not do.
• Three stages in one unit. Sediment, catalytic carbon and scale control, pre-assembled and ready to plumb in.
• No salt, power or drain. Nothing to refill, no electrical connection and no drain line, so it fits where a softener will not.
• A 0.5 micron particle cut. The catalytic block is the finest carbon we make in this size, which keeps more off the cartridge behind it.
• Calcium and magnesium stay in your water. They are conditioned, not stripped out.
• Gauges fitted as standard. You can see the pressure drop across the filters and change cartridges on evidence rather than guesswork.
• WaterMark certified. Certificate No. 23247, so a licensed plumber can install it.

This system next to a salt-based softener

	ScaleSoft®	Salt-based softener
Salt to buy and refill	None	Regular top-ups
Sodium added to your water	None	Yes
Calcium and magnesium	Stay in your water	Removed
Power connection	Not needed	Required
Drain connection	Not needed	Required
Water sent to backwash	None	Yes, on every regeneration
Ongoing upkeep	A cartridge change, about every two years	Salt, servicing and regeneration

Important notes

ScaleSoft® conditions water to prevent and reduce scale, but it does not remove calcium or magnesium from the water. You may still see these minerals on surfaces where water is allowed to dry. Those deposits are less adherent and easier to clean than untreated water. On glass shower screens, squeegee or dry the glass after use to prevent spotting.

ScaleSoft® reduces the formation of hard mineral scale. It is not a disinfection or purification device, and it is not an ion exchange water softener. Suitable for mains and treated water.

Hardness figures. The ceiling quoted for the scale-control cartridge is carbonate hardness, which is not the total hardness that water authorities publish, so your supply's figure should not be read against ours. Send us your report if you want it checked.

This model does not target heavy metals. If lead or other heavy metals are part of your specification, GT1-SS-20B-LRC carries a metal reduction block in the same position.

For the full technical specification and installation information, see the Specs/Performance tab.

System contains

• 3x 20" x 4.5" high flow housings, pre-assembled on a stainless steel bracket (GT1-9TWMS)
• 1x Sediment cartridge, 5 micron polyspun (stage 1)
• 1x Catalytic Carbon cartridge, 0.5 micron catalytic coconut carbon block (stage 2)
• 1x ScaleSoft® cartridge, salt-free scale control (stage 3)
• Pressure gauges fitted before and after the filters (GT16-3S)
• Opening handle to suit 4.5" housings (GT17-2S)

Other water supplies

Water from a private or untreated supply can carry a wide range of contaminants, and we cannot recommend a cartridge set for one without a current water analysis. Contact us and we will point you to the analysis service.

WaterMark certified

This water filter system is certified to WaterMark Standard AS 3497 under Certificate Number 23247. WaterMark certification is a mandatory requirement under Australian law for water filter systems to be installed by licensed plumbers. Products bearing this certification meet rigorous Australian plumbing and water safety standards, ensuring compliance and reliability. Our WaterMark-certified filter systems are hand-assembled in Australia and undergo random batch testing to maintain the highest quality and workmanship, giving you confidence in the safety and performance of your water filtration products.

ScaleSoft® is a product brand of High Performance Filtration.