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Finerfilters 5 Stage Domestic Reverse Osmosis Under Sink System with Diaphragm Booster Pump (50 GPD)

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Finerfilters 5 Stage Domestic Under Sink
Reverse Osmosis System with Diaphragm Booster Pump


Reverse Osmosis is a technology that is used to remove the large majority (98%+) of contaminants from water. The Reverse Osmosis system works by pushing the water under pressure through a number of increasingly smaller filters and finally through a semi-permeable membrane, essentially trapping all contaminants.

Finerfilters are here to support you before and long after you buy. We provide help through manuals, easy install guides, diagrams, phone & email support.

This system produces up to 190 litres per day of purified water and comes complete with:

A 3 US gallon pressurised storage tank holding 6.5 litres of RO filtered water.

Installation Manual.

Chrome Faucet Tap.

All pipes, pre-filters, post filters, and fittings required for easy Installation.

Booster Pump with high and low pressure switches.

The membrane can last between 1 and 2 years dependent on water hardness. Filters to be replaced every six months.


Please note:

This system requires a minimum of 29 PSI (2 BAR) to work.
A minimum of 29 PSI (2 bar) is required to operate the booster pump.
Ideal pressure depends upon incoming water temperature but around 60 PSI (4 BAR) is acceptable.

Reverse Osmosis Systems waste water to make water, and this should be done at a high pressure as the water is being forced through microscopic holes which catches contaminants. 

This is normal and the same with all RO systems as this is the way the membrane rejects the impure water, which goes to the drain, to produce the pure water.

The system works optimally at 80-90 PSI (5.5 – 6 bar), and to get to the quoted output, we’d recommend running the system on or around this pressure.

This allows the system to reduce the waste water to pure water ratio and work quicker at producing pure water.

As many people won’t have this mains pressure; pumped RO Systems or booster pumps can be purchased from us and added to the system which will increase the pressure output (a minimum of 29 PSI (2 bar) is required to operate the booster pump).
Please ensure that your incoming mains water pressure meets or exceeds this before purchasing.

Finerfilters Domestic Undersink 5 Stage Reverse Osmosis System (50 GPD)

The 5 stages of filtration are;

Stage 1

A 5 Micron Sediment Filter Made of 100% Pure Polypropylene Fibres. Removes Dirt, Sand and Rust.

Stage 2

A Granular Activated Carbon Filter Composed of High - Performance Activated Carbon. Removes Free Chlorine, Odour, Organic Contaminants, Pesticides and Chemicals.

Stage 3

A Carbon Block Filter Composed of High Performance Carbon. Removes Trihalomethanes, Pesticides and Volatile Organic Chemicals (VOCs).

Stage 4

A High Rejection Thin Film Composite 50 GPD Reverse Osmosis Membrane with the Capacity to Produce up to 190 Litres of Purified Water per day. This Membrane Removes Contaminants Present in Water Including, up to 99% of Dissolved Salts, Lead, Copper, Barium, Bacterial By-Products, Oestrogen and Silica.

Stage 5

A Post Carbon Filter Designed to Improve Taste. It Removes any Residual Impurities and Odours from the Tank and Provides a Finer Conditioning of the Purified Water.

Plastic Water Storage Tank

Made of food grade reinforced Polypropylene.

Contains a food grade Butyl diaphragm/bladder which holds the water, ensuring tasteless, odourless & contaminant free water.

This tank is an air bladder tank meaning the water does not touch the metal outer shell, but rests in a Butyl bladder. There is a small air charge between the outside of the bladder and the inside of the tank. It’s this air pressure that pushes the water out of the tank when the tap is opened.

The tank is pre-charged with air but will require topping up as part of the regular maintenance of your reverse osmosis system. Air can be added using a bicycle pump or similar.


This tank can be connected to additional tanks to increase the storage capacity on your Reverse Osmosis system.
Tank uses ¼” Female x ¼” Pushfit Angled Shut Off Valve.
Plastic tank holds 6.5 litres of water.

Working Pressure: 50 PSI

Bottom Air Charge Pressure: 5-7 PSI

Dimensions: 36cm x 25cm x 25cm

System Measurements

5 Stage Reverse Osmosis System (With Pump)

Length 41cm
Width 26cm
Height 50cm
Weight 13kg

Approximate percentage (%) of contaminants removed by Reverse Osmosis.

Aluminium: 96 - 98

Lead: 95 - 98

Ammonium: 80 - 90

Magnesium: 93 - 98

Bacteria: 99+

Manganese: 96 - 98

Boron: 50 - 70

Mercury: 94 - 98

Bromide: 90 - 95

Nickel: 96 - 98

Cadmium: 93 - 97

Nitrate: 97 - 99

Calcium: 93 - 98

Phosphate: 95 - 98

Chlorine: 98+

Potassium: 92 - 96

Chloride: 92 - 95

Silica: 80 - 90

Chromate: 85 - 95

Silicate: 92 - 95

Copper: 96 - 98

Silver: 93 - 96

Cyanide: 85 - 95

Sodium: 92 - 98

Fluoride: 95 - 98

Sulphate: 96 - 98

Hardness: 93 - 97

Thiosulphate: 96 - 98

Iron: 96 - 98

Zinc: 96 - 98


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Product Display Name Finerfilters 5 Stage Domestic Reverse Osmosis Under Sink System with Diaphragm Booster Pump (50 GPD)
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