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Reverse Osmosis

Reverse Osmosis Water Filters – 

What Is Reverse Osmosis?

Reverse osmosis works by having a high water pressure on the incoming supply side of a semi-permeable membrane within the water filter. This causes the water molecules to pass through the membrane leaving behind salts and other contaminants that were in the water and resulting in purer water on the resevoir/tap side with the rejected water containing the impurities being discharged in to the drain.

A properly functioning RO system will normally achieve a reduction of between 94-99% depending on the impurities concerned (see below). 

[The capacity of the membrane is expressed as GPD which means Gallons Per Day]


How Reverse Osmosis Water Filters Work

How do Reverse Osmosis Water Filters Work?

Filter 1)  The sediment filter is the first stage and removes particles and suspended sediments and particles to 5 micron.

Filter 2)  The Pre-carbon filter then removes dissolved gases and heavy metals.

Filter 3)  The RO Membrane removes impurities to 0.00001 Microns. It does not store them in the filter but washes the impurities down to drain.

Step 4)  Purified water is stored in a 10 litre storage tank.

Filter 4)  The system automatically shuts off when the tank is full and then passes through a final post carbon filter to provide taste and odour optimisation for the finishing touch. Other post filters can be used to further condition the water for optimal health, such as alklaine ionisation, negative oxidation and micro-clustering.

Example o Typical Removal Rates:

ION Removal(%)
Calcium 93-98
Sodium 92-98
Magnesium 93-98
Potassium 92-96
Manganese 96-98
Iron 96-98
Aluminium 96-98
Copper 96-98
Nickel 96-98
Cadmium 93-97
Silver 93-96
Zinc 96-98
Mercury 94-97
Chloride 92-95
Ammonium 80-90
Bromide 90-95
Phosphate 95-98
Cyanide 85-98
Sulfate 96-98
Thiosulfate 96-98
Silicate 92-95
Nitrate 90-95
Borate 30-50
Fluoride 92-95
Chromate 85-95
Lead 95-98
Hardness: Calcium & Magnesium 93-97
Radioactivity 93-97
Polyphosphate 96-98
Orthophosphate 96-98
Silica 80-90
Boron 50-70

Reverse osmosis membrane

Typical Reverse osmosis installation:

reverse osmosis installation

What Are The Benefits of Reverse Osmosis Water FIltration?

In combination with carbon filters, the removal of chemicals such as chlorine means you’ll experience much better tasting water & you’ll probably find yourself drinking more of it! Enjoy the benefits of pure water directly from your kitchen tap. No need to buy expensive bottled water of questionable quality Only normally require a filter change between 9-12 months which can be easily done by anyone. Replacement filters are readily available and very economical With a huge range of contaminants being removed, knowing that you and your family are benefiting from pure, safe, healthy water at all times is priceless.

A concern that is sometimes raised over reverse osmosis water filtration is that this method also results in the beneficial minerals such as calcium & magnesium being removed along with the undesirable elements. There is considerable debate as to how important an issue this is with claims varying from it being a major health concern to being of no consequence. In response to this issue many reverse osmosis systems on the market now include alkaline re-mineralising filters which ensure that any beneficial compounds removed in the purification process are replenished, giving you the best of both worlds and the best tasting, healthiest water possible.

Types of Reverse Osmosis Systems

Most RO systems offered for sale will include a tank which is located under the counter and holds the purified water until required. There are some reverse osmosis filters however which are known as ‘direct flow’ which have the capacity to, as the name suggests, provide a direct flow of purified water from the filter unit to the tap. The main benefit of such systems over the standard type is fresher water and space saving as they do away completely with the need for a storage tank. Such systems include the excellent Osmio HT+ Home & Office RO Filter with smart water functions.

For those who want enjoy the advantages of reverse osmosis but are regularly on the move, in rented accomodation or don’t want to be bothered plumbing in a RO system there is now the option of the countertop Osmio Zero Installation Reverse Osmosis Water Filter requiring nothing but an electrical socket. This innovative and stylish kitchen worktop RO filter will supply ambient, warm, hot & boiling purified water at the touch of a button and can completely replace the kettle.

Osmio Zero Installation Countertop Reverse Osmosis System

Another factor to consider is your home’s water pressure ~

Do You Need a Pumped or a Non-Pumped System?

If you have normal to high water pressure of 3 bar or more, then you should use a non-pumped system. If your water pressure is lower than 3 bar or you are not sure, we recommend you use a Pumped system.

Pumped reverse osmosis systems come with a normal UK 3 pin plug and just need to be plugged into a nearby electrical socket. If you have any appliances (dishwasher, washing machine etc) next to your installation area (usually under the kichen sink),  then it is normally very easy to find a plug socket there. Pumped systems are very quiet and very low power. We can also supply stand alone pumps for upgrading existing RO systems.  

Buy With Confidence

Our Reverse Osmosis water purifier systems are made in Europe & the US to the highst quality standards and are NSF or WQF certified internationally for total peace of mind. Browse the range and order on-line and if you so choose, you can buy spare replacement filters at the same and save money on your first filter change. The average annual cost for replacing filters is highly economical at around £50-60, so order yours online now and choose from our range below.

All our systems are covered by our 30 day no hassle return guarantee* as well as the manufacturers guarantee and are delivered free (UK mainland) by courier

 If you have any questions regarding the best choice for your situation please contact us on the chat form below or phone us on : 020-3507-1879

 * terms & conditions apply

For the full range of replacement Reverse Osmosis filter cartridges click here

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