What is reverse osmosis?
As the internet evolves, there is growing public awareness of water contamination.
All around the UK, water is recycled and treated by regional water facilities, over and over again. Pollution impurities, human neglect, and the growing increase in the pharmaceutical drugs we take, in addition to sediments and minerals, continually degrade the quality of our water.
In the USA, water treatment provided to homes is often more basic than in the UK, and it is usually left to the home occupier to organise the treatment of their water for drinking water and consumption purposes.
Depending on the nature of the local water, the choice of water treatment can be numerous. There are many different types of products and filtration processes on the market today, with a gigantic number of products coming into the UK from China.
Filter housings, cartridges, distillers and drinking water systems are now developed at low cost, and some are more high running-cost and high-maintenance than others.
Another very popular alternative to treating your own water is to buy bottled water. However, with the growing awareness of plastics in our oceans, single-use bottled water is beginning to become less popular, particularly with the younger eco-warrior generation.
The reverse osmosis process will purify water and make it safe for consumption by removing contaminants using a specialised water filter called a membrane.
This membrane is an ultra-fine strainer that removes impurities from the water, including; dirt, bacteria, pharmaceuticals, pesticides, heavy metals and chemicals.
The water is subjected to pressure that helps to separate the good pure water from the impurities.
The 98.8% purified water goes to your drinking water faucet or 3-way tap, leaving behind the impurities which are then flushed safely down the drain. This results in clean, refreshing and safe water that is free from harmful substances.
Reverse osmosis can be utilised in various settings, including households, medical & dental facilities, factories, hospitality outlets and industrial facilities, ensuring that safe and clean water is available wherever required.
Don't we need the minerals in our drinking water?
With regard to removing minerals from drinking water, we get an insignificant amount of minerals from our drinking water. In fact, you would typically need to drink 30 litres of water daily for adequate mineral intake.
Instead, we obtain most of the mineral content our bodies need from our diet. Dairy products are the best source of calcium, as are dark green leafy vegetables and nuts and beans. Plant milk, breakfast cereals and bread are often fortified with calcium.
Interestingly, I note that many of the doctors and dentists in our customer base have opted to install reverse osmosis systems into their homes.
What does reverse osmosis remove?
Residential reverse osmosis systems typically remove 98.9% of all impurities but can be as high as 99.9% in more specialist conditions, such as dentists, medical applications, window cleaning, factories and laboratories.
The RO system removes the contaminants we don't want in our water supply by rejecting those to the drain.
In a typical domestic home, here is what RO will remove:
Let's tell you more about the filters and running costs
An RO System consists of multiple pre-filters (shown as 1, 2 and 3 in the image below), which are needed to filter out sediment and chlorine, which protects the membrane (shown as number 4 below).
The membrane does all the work and is also the most expensive filter to replace.
So, the best way to protect the membrane is to ensure your RO filter is installed on softened water. A membrane of an RO system installed on hard water will typically last three years, whereas a membrane of an RO installed on softened water will typically double, so 6-7 years, or more!
Some RO systems have only three filters (shown as 1,4, and 5 in the image below), but some have five.
On the more budget RO systems, the more filters, the better the water quality. But be warned, more filters mean higher filter replacement costs each year!
Strangely enough, on the premium machines, it works the other way around:
- They typically have a better quality filter and have just three filters
- LOWER RUNNING COSTS
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What about remineralising filters?
Sometimes customers are recommended by other companies to fit a 6th filter, called a ‘Remineralising’ filter.
This filter basically adds back calcium and magnesium, and is effectively a block of chalk within a plastic housing.
As a rule, I don’t recommend these except for circumstances where a customer specifically wishes to alter the taste of the water. RO water can taste sometimes too pure, just as like some people find that drinking softened water can taste slightly sweet - the remineralisation filter adds back the chalk and as a result changes the flavour of the water (I've heard the customers use the description of the water tasting 'fuller' and 'more minerally' - but be warned, they will add back scum to hot drinks and some scaling to the kettle.
The amount of beneficial minerals they re-add is, however, so insignificant that you would have to drink around 30 litres of water a day for the filter to become effective.
(We feel they are there to take money out of your pocket and put that into the filter company's pocket).
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Here is how a typical domestic RO system works:
Reverse Osmosis System Range
Low-Efficiency RO Systems
These small, low-volume budget reverse osmosis systems are available in simple 3-stage, 4-stage or 5-stage systems, depending on the preference of the final water quality.
The upside of these budget RO systems is that they are cheaper to purchase. The downside, however, is they are heavier on water usage.
Option A: 3-Stage RO System