Reverse Osmosis Water Filter System Wiki

Reverse osmosis is a water purification technology process that removes large particles, salt, unwanted chemicals, color and odors from drinking water using a semipermeable membrane. A reverse osmosis water filtration system reverses the osmotic process of moving a solution from an area of lower concentration to an area of higher concentration. In a reverse osmosis water filtration process, the water is moved from an area of higher concentration to an area of lower concentration through the application pressure. Through this process, the well water or tap water is rid of different kinds of impurities such as bacteria, dissolved metals, chemicals like chlorine, fluorine and other unwanted particles. Bacteria and other unwanted microorganisms are also prevented from entering the tank containing clean water through the reverse osmosis process.


A RO water filtration system

A reverse osmosis filtration system comes with filter and membrane which allow only solvent to pass through it to the other side of the system. Solute and large molecules or ions are prevented from passing to the other side. They remain at the pressurized side of the system. Reverse osmosis filtration system has different applications. It can be used in the industry for certain industrial process. But today, there are RO systems that are meant for home use. Individuals and families can buy such systems and install them under their kitchen sink or any other suitable tap where they obtain their drinking water. Commercial establishments like restaurants and companies can also install RO systems under the tap from where their staffs obtain their drinking water. If you are looking for a way to purify your home drinking water, installing a RO system is the way to go. Before placing an order, it is important that you know more about this system.



For understanding clearly about a Reverse Osmosis system, read below article from our experts.

Components of RO System

There are different makers of RO systems nowadays. Though, each product has its own unique features and qualities that differentiate it from other products, there are certain components that are common to all reverse osmosis system. Below are the common components of RO systems.

1. Cold Water Line Valve

As implicit from the name, water is supplied to the RO system through this component which is fitted on the cold water supply line. The valve features a tube that is fitted to the RO pre filter’s inlet side.

2. Pre-filter (s)

Water first enters the pre filter of RO through the cold water supply line. There are some RO systems that have more than one pre-filter while there are some that have only one pre filter. Pre filters are available in different types. There are sediment filters and carbon pre-filters. The former which is the most commonly used gets rid of sand silt, dirt and other sediments from the drinking water while the latter is used to get rid of chlorine which can damage the thin film composite (TFC) and thin film material (TFM) membranes of the system.

3. Reverse Osmosis Membrane

The membrane is an important and focal part of an RO system. It is available in several types with the spiral wound type as the most commonly used type. There are two types of the spiral wound, namely, the TFC/TFM which does not tolerate chlorine and the CTA (cellulose triacetate) which tolerates chlorine.

4. Post filters

As implicit from the name, the post filter is the filter that removes unwanted particles, odor and colors that have not been removed after the reverse osmotic process has been completed. This filter is normally carbon but it can either be carbon block or granular form. The purified water is kept in the storage tank. However, before the water passes through the RO faucet, it has to pass through the post filter for the remaining unwanted particles to be removed.

5. Automatic shut off valve (SOV)

The automatic shut off valve stops the water production or water flow into the reverse osmosis system when the storage tank is filled up to the brim. The shut off valve opens to allow further water production once water is taken from the storage. This is because the pressure in the storage tank reduces whenever water is no longer filled up to the brim. The automatic shut off valve helps to make use the system very comfortable and easy. You don’t have to be checking the system always to see when it has been filled up. It also helps to conserve water as it prevents water wastage. If this feature is not present, when the storage tank is filled up to the brim, the water will start following out of the tank flooding the floor until it is locked. This will definitely leads to water waste.

6. Check Valve

This features situates at the end of the housing of the RO membrane. As the name already tells you, this valve helps to prevent the water in the storage tank from flowing backwards which can damage the membrane of the RO system.

7. Flow Restrictor

This is the feature that controls the flow of water through the membrane of the RO system. The flow restrictor is available in a number of styles. The flow control is a very important component of the RO because it helps to keep the pressure on the side of the inlet of the membrane so that more water will be produced. The flow control which is located in the drain line tubing of the RO prevents the incoming tap from taking the least resistance path and flowing down the drain line.

8. Storage tank

This is the tank that contains the purified water before it is drawn from the faucet for drinking or cooking. The tank capacity differs from product to product. However, normally, it is meant to hold up to 2.5 gallons of water. The storage tank features a bladder inside which helps to maintain the pressure of the water in the tank when it is filled up.

9. Faucet

The RO system comes with its faucet rather than using the kitchen faucet. The faucet of the RO system is installed on the sink in the kitchen. An air-gap faucet is generally utilized in locations where plumbing codes are required.

10. Drain line

This is the line that runs to the drain from the end of the outlet of the RO membrane housing. The impurities, unwanted particles and chemicals sifted from the water are eliminated from the system through this feature.

There may be other components of reverse osmosis depending on the model you are using. So, the above mentioned components are not exhaustive. However, they are the essential components.

The process of RO


The filtration process of a RO system

RO system is a unique water purification system thanks to its efficient and unique water purification process. It is its purification process that differentiates it from other processes. The reverse osmosis filtration system has two parts separated by the cellophane-like membranes. One parts contains contaminated water and the other part contains purified water. The water purification process of RO is quite different from the water purification process of osmosis water purification system as well as that of distillation process. Here, pressure is applied on the part of the system that contains contaminated water causing it to move from the pressurized part to the side with lower pressure. When pressure is applied to the side containing contaminated water, the impurities will be prevented from passing the system. Only clean water will pass to the storage end. Through the process impurities, particles larger then .001 microns and microorganisms are removed from the drinking water.

The purified water will be push to the storage tank of the reverse osmosis system which has lower pressure than the first part of the system. The large particles that are not allowed to enter the storage system is pushed out of the system through the drain system. However, this does not conclude the process. There is also post treatment or filtration process. The post filter will further rid the water of any remaining impurities, color and odors that were not removed during the initial filtration process. The post treatment starts when you open the faucet to fetch water from the tank. In this way, the water that comes out from the faucet is completely pure. There are some products that come with demineralization feature. This feature will add useful minerals to the water to make it healthier and rich for human consumption. The demineralization process will also enhance the taste of the water.

Is reverse osmosis water safe for drinking?


As mentioned above, RO system removes impurities, particles, metals and dangerous chemicals from drinking water making it to be pure for human consumption. However, there is controversy on whether water filtered with a reverse osmosis system is good for human consumption. The opponents argued that reverse osmosis de-mineralizes the water, that is, it removes useful minerals together with impurities from the water. This argument may sound plausible but it does not take into consideration the point mentioned above that many reverse osmosis system come with remineralization feature which adds useful minerals to the drinking water making it healthy for consumption and also enhancing its taste.
Drinking water purified by a reverse osmosis can give some advantage. It is a good option for people living in area with heavy herbicides and pesticides. If the tap water in your area contain some impurities or chlorine, you can use reverse osmosis system to get rid of the impurities from the water. It is also good for people living in parasite and bacteria-laden water as it can remove these microorganisms from your drinking water.
It is true that a reverse osmosis system may remove useful elements from the drinking water but that does not constitute much problem to your health. It will be better for you to drink de-mineralized water than to drink water that contains impurities, disease causing microorganisms and chemicals. Besides, there are other ways through which we obtain minerals such as calcium, fluoride, manganese and others that are removed from the water through filtration. If you consume a well-rounded diet and eat enough vegetables and fruits you will be able to obtain these minerals from them.
You can give water produced by a reverse osmosis system to your children. However, owing to the reasons mentioned above, you have to make sure that you nourish them with foods, fruits and vegetables that are rich in vitamins especially fluoride which they require for the growth of their teeth. Besides, when you want to buy a reverse osmosis system, it is advisable that you look for a type that comes with demineralization feature so that these important minerals will be added again to the water to make the it completely good for human consumption. If the water is remineralized, it will no longer lack in essential elements and your kid will obtain enough fluoride and other minerals they need for proper body functioning from their meals.
In summary, it is advantageous to drink water filtered by reverse osmosis. It is better to drink it than to drink dirty water as a lot of deadly infections and illnesses can be gotten through drinking water. Secondly, make sure that your reverse osmosis has remineralization feature. If reverse osmosis is not good for filtration of water, the American troops would not have used it to desalinate the drinking water of their troops. It is also utilized by some countries during relief and flood remediation efforts.

Advantages and Disadvantages of reverse osmosis

Reverse osmosis is not the only filtration process through which dirty water can be purified or turn into fresh water for drinking. The questions that should be asked here are: how does reverse osmosis filtration system compare with them? Does it have any edge over them? Is it better to use it than to use other filtration system?

When compared with distilled water or bottled water, there isn’t much difference with regard to the acidic level of both water. Both distilled water and water produced through reverse osmosis are somewhat acidic. Both system produced clean water. However, reverse osmosis has no effect on the atmosphere or environment as bottled water. This is the edge it has over the consumption of bottled water. The consumption of bottled water results in more and more plastic waste in the landfills. It is expensive to manage the landfill. Besides, having a lot of plastic waste gets the landfill easily filled up. Reverse osmosis does not produce any plastic waste. It is as simple as fetching water from your tap.

Reverse osmosis filtration is not difficult to install and use. There are household sizes that one can easily buy and install under the sink of their kitchen or any other suitable for fetching drinking water. Its ease-of-use, maintenance and installation give it an edge over some other water purification systems that are available for use in industry. A water distiller makes use of electricity to purify water and thus may have more mechanical and electrical parts that may require much maintenance. Besides, it can be more expensive to use distiller. Since they make use of electricity, they can increase your electric bill but RO makes use line pressure from your home’s plumbing. It does not need any electricity and thus will not increase your electricity bill.

How to choose your reverse osmosis water filtration system: what to consider

When it is time for you to buy a reverse osmosis system, there are a number of factors that you should put into consideration. Here are some of the factors that you should consider if you want to choose the best system.

Consider the level of the cleanliness of the water you want to purify: It is necessary that you consider how clean the water you want purify is before you choose a reverse osmosis system. This is because by knowing how clean your well or tap water is, you will be able to choose the right RO system with the right number of filters that will be able to get the impurities out from the water. If the contamination level of the water is higher, then more filters will be required. There are home test water kits that you can use to determine this. Alternatively, you can also contact the water authority of your area to perform the test for you.

Consider the frequency at which the filter will be changed: It is advisable that you buy a product that come with filters that will last for a long time before it will be changed. In this way, you will not spend much money changing the filters on regular basis. You should also consider how easier the changing of the filter is. It is better to buy a product whose filter housing is changed completely after a long time of usage. If you buy such filters, you will not require much expertise to change the filter since you will be removing the entire housing and replacing it with new one.

The cost of the product: You should also consider the cost of the product. There are a number of factors that affect the cost which include the number of filters it has, the size, durability, performance and warranty. Look for a product that is within the price of its class. If a manufacturer claims that his product has all the features and many filters and yet, he is selling it at a very reduced price, you should be wary in buying such a product because products with great features and many features are normally expensive.

Consider the quantity of water product: This depends on your family need but a good product should be able to produce at least a gallon of water per day or per person.

Other factors to consider are:

  • The potability of the water filtered
  • The quality of water produced during the pretreatment stage
  • The TDS level of the water produced which should be below 500
  • The chlorine level of the water source (if the water is chlorinated then you should buy a type with membrane that is not sensitive to chlorine but if the water source does not have any chlorine, then you should buy a type with TFC membrane that can withstand bacteria attack)
  • The acidity level of the water produced
  • Performance factors (the performance of a RO system is affected by a number of factors which include temperature, incoming water pressure, the quality of the filters and membranes used and the TDS number)

And one last step: take a look at top six best reverse osmosis system reviews 2015!

How to increase the gallon per (GPD) capacity of your reverse osmosis

To ensure that you have constant supply of clean water in your home especially during the time of heavy usage or when the water in the storage goes to different locations, it is advisable that you know how to increase the gallon per capacity of your reverse osmosis. The good news is that changing to a higher flow membrane will not affect the quality of water filtered by your RO. It is very easy to replace your flow membrane with a higher one. Just get the right match higher capacity membrane and replace it with your old one. The higher capacity membrane will increase the gallon per capacity of your RO without affecting the quality of water produced.


Water is a very important element required by human beings as well as other animals for survival. However, it is not every water that is good for human consumption. If you want to enhance the quality of your health, you need to drink clean water. But it is difficult to get it. You can easily obtain clean water by installing reverse osmosis system in your home. With it, you will be able to get rid of impurities from your drinking water.