PSI-021-5RM 5 Stage Re-Mineralizing, Oxygen rich alkalising

This Reverse Osmosis Undersink 5 Stage model PSI-021-5RM is a premium low waste 1 to 1 ratio unit featuring the exclusive membrane flushing with a full size re-mineraliser.

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This is a premium system made from the finest quality parts available without compromise.

This Reverse Osmosis Undersink 5 Stage model PSI-021-5RM is a premium low waste 1 to 1 ratio unit featuring the exclusive membrane flushing with a full size re-mineraliser.

It has the Dow Filmtec 300 litre per day TFC membrane, the 300 litres is rated at 50 psi (350 kpa) but will produce up to 450 litres per day higher pressures, what this means is the system will fill faster than most systems on the market. This system has an auto shut-off device that closes off the in-feed supply when the storage tank has filled.

All components are NSF certified to standards 042, 053 & 058

Replacement trio of cartridges (ROCDU-02) which is the annual change are $55.00

See faucet (tap) range, click here to view.


Supplied with QMP-300-HP U.S.A. made housing 10" Australian Standards AS3497 with 1/4" NPT threaded ports. This housing is tough with a burst strength of 575psi (4000kpa) and is tested to AS3497 which means it has been tested from 0 to 700kpa and back to 0 kpa 100,000 times without failure, cracking or distortion.

With these premium systems we supply the 550kpa pressure limiting valve with dual check valves which is a plumbing code requirement, the valve is also Watermark AS1357-2 licence no 23133 as the watermark is also a plumbing code requirement.

We supply the 550kpa PLV with the premium system so the filter system runs faster than other units on the market.

Click here to download a sample of the installation instructions in pdf format

Highest Quality QMP-300 US housings, standard size 10 inch (9 ¾" (248mm) NSF certified (worlds leading certification authority) NSF/ANSI standard 042 certification, also tested and certified to Australian Standards 3497

Removes 98% of Fluoride.

For membrane treatment rates click here.

Click here to jump to the re-order for the correct annual trio pack of cartridges.

Click here to jump to the re-order for the correct membrane changed usually at the 4th year.

Click here for re-mineraliser needs emptying and re-filling every 4th year

1 Micron food grade polyspun sediment filter 9 ¾" (248mm) (standard size) U.S. made

Omnipure OMB934-5M coconut quality carbon cartridge 9 ¾" (248mm) 37,000 litres chlorine rating, U.S. made

Genuine Omnipure CL10RO- Coconut carbon post filter, highest quality possible. U.S. made

Genuine Dow Filmtec TFC Membrane (standard by which all other membranes are measured)

The re-mineraliser (Alkalizer) which contains crushed Marble and or crushed Limestone, it's primary function is to balance the pH to neutral as reverse osmosis water is slightly acidic because the process removes the calcium from the water which acts as a ph buffer. The material contained in the cartridge is a sedimentary rock which is mostly calcium but also contains trace elements of other minerals, we are prevented from supplying a specification sheet as the amount of re-mineralisation is dependant on the pH of the water, if we had the unit tested at say a pH of 6.0 the cartridge would result in an X factor of re-added minerals which would be misleading if the water in your unit on your water supply had a pH of say 6.4 before the re-mineraliser which would result in a lower added amount. The amount of re-added minerals is totally dependant on the pH of the water out of your system so in short the higher the pH the lower the amount of re-added minerals and the lower the final pH the greater the amount of re-added minerals.

The reverse osmosis process can't pick the pepper out of the salt so to speak, so it is better to be sure and remove all the poisons from the water than be worried about the minerals that have been removed. Health experts say that you obtain the minerals that your body needs from your diet. You should not rely on water as a mineral source as there is very little available to the body in water as the minerals are totally dissolved, the re-mineraliser in this system is about balancing the pH as a taste issue.

The re-mineraliser cartridge in this unit can be un-done and some of your own media can be added if you wish.

Main filter unit size, 42 cm high, 42 cm wide & 14 cm deep. 9 litre stainless steel storage tank (exceeds drinking water guidelines) NSF Certified. If space is an issue we also offer a 4.2 litre or 12 litre tank.

Click here for tank details.

Premium systems now have the lowest waste ratio of all systems on the Australian market, using a Patented combination membrane flushing valve/flow restrictor means the waste ratio is about 50% less waste than other brands, waste ratio is now about 1 to 1.

Click here to obtain more information about waste ratios

Installation choice 1/2" tee olive fitting, 3/4"dishwasher adapter or 1/2" easy fit braided line flick mixer adapter, our systems take the average handyman 1/2 to 1 hour to install

Mains connect systems; click here to view how each are installed water filter parts

550 kpa pressure limiting valve, genuine QMP Stainless Steel dedicated faucet. Housing spanner to ease cartridge changes.

10 year warranty

Click here for selection Advice

PSI Systems are Better Than Other Brands, click here to find out why

If you option to have the hand held TDS meter with the unit beware that the system will have an elevated reading due to having the reminerliser cartridge.

All reverse osmosis systems require a minimum pressure of 40 psi (280kpa) with 50 psi (350kpa) or more is ideal. If you are unsure what your pressure is check with your local Council or water authority.

Product comes complete, ready for installation.

Substance treatment rates below for TFC reverse osmosis, click here for a full list in PDF.

Product Details

Data sheet

10 Years Warranty
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