Types of Reverse Osmosis Water Filtration Systems

Choosing RO SystemThings to know about RO water systems and filters: the way they work, types, pros and cons.

Reverse Osmosis water, or RO water, is resulted from a purification process called the reverse osmosis water filter. Feeling not quite familiar with this type of water filter? Continue your reading because this article covers all you may need to know about the reverse osmosis water filtration systems.

You will see what exactly reverse osmosis means and how the process of RO water filter works. You will also know the advantages and disadvantages of using RO water treatment. Moreover, you will learn that there are several types of reverse osmosis filters sold in the market these days. Bottomline, you will be well-informed before you decide to buy one or if RO water is really right for you.

What is Reverse Osmosis?


reverse osmosis filtration

Osmosis is actually an old and natural process in nature, in which fluid has a tendency to migrate from low solute concentration to the higher one. Reverse osmosis, as the opposite, is an artificial process in which the fluid is forced to move from the high solute concentration to the lower one. A semipermeable membrane is used in the process and there is pressure applied in excess of the osmotic pressure. The membrane consists of the dense layer that is supposed to only allow water to pass. Since other solutes are prevented from passing the membrane, the water resulted is expected to be clean and purified.

The RO filtration itself isn’t really new, since the method of reverse osmosis was first developed for desalinating seawater. Now, the same technique is used for the reverse osmosis water treatment. Many countries around the world have adopted this very water treatment as their new alternative of water filter. Being such a hit, RO water filter must have something that sells to people.

3 and 5 Stage Systems


Watts Premier Five Stage Reverse Osmosis Water Filtration-SystemThe premier reverse osmosis consists of several stages along in the process, in order to produce some clean water. Early in its production, there was only 3 stage of RO system, but now it has become 5 stage reverse osmosis system. Many RO system units sold in the market today have adopted this 5 stage RO system. It is said that drinking water resulted from the Watts premier 5 stage RO system is like drinking a bottled water.

The 5-micron filter of the system reduces dirt, sand, and sediment contained in the water. To follow that, the carbon block filter of the system reduces chloramines and chlorine, meaning reducing sharp taste and odors. The second carbon block reduces again the hard to remove contaminates, such as chloramines. After that, the RO membrane filters out impurities such as arsenic and lead. Not only that, the membrane also dissolves solids and other contaminants. The final filtration in the system makes sure that the resulted water clean and fresh to consume.

What is a Micron?

Sediment 5-Micron 1-Micron Carbon Filter Reverse-OsmosisFor the openings between pieces of the filter media, the average size is measured in microns. For example, a 20-micron filter has larger openings if compared to the 5 micron one. Consequently, a 5-micron filter has larger openings compared to the 1-micron water filter. The larger the openings are, the more likely components are able to pass through the membrane filters.

Most of the RO water treatments sold in the market employ the 5-micron filter. That size is considered good already. But of course, you could always go for the best, which is the 1-micron.

What are the Advantages and Disadvantages of RO Water?


The advantages of using an RO water filter:

  • You will get much cleaner and fresher water. The water has gone through some filtration and purification, in which minerals and other harmful components have been removed along the process. In the long run, you will have more energy and stay healthy.
  • You will get better smelling and better tasting water. Since some minerals have been removed, the RO water will not smell like iron, let alone taste like one. With better smelling and better tasting water, you will come to drink it more regularly each day.
  • You will get healthy water that costs you less than the bottled one. If compared to those commercial, bottled water, the RO water wins in the term of being economical. For the quite same clean water, you pay less with the RO water. This is a clean and cheap solution to turn from the tap and bottled water.

The downside of using it:

  • You will be drinking demineralized water. As stated before, the filtration process removes minerals that are originally contained in the water. Although dangerous components are removed, not all minerals are harmful to the body. Some people think that drinking demineralized water is not the best option.


On the other hand, water isn’t the only source of minerals and you can easily get it from natural sea salts, foods, vegetables and so on… A lot of nutritionists agree that water isn’t a primary source of dietary minerals anyway!

You can’t drink sufficient water to get your daily suggested allowance. Moreover, minerals in water are inorganic, it’s not easily absorbed by the body however organic minerals in foods are more readily absorbed. If you still concerned about minerals in water than Aquasana Reverse Osmosis AQ-RO-3 OptimH2O with remineralization technology will be your choice!


  • You will be drinking rather an acidic water. With the minerals being removed, the purified water will come out rather acidic. Although it also depends on the water source, most likely rather acidic water will be resulted from the RO filter.
  • You will be wasting a few gallons. Although the process resulted in clean and fresh water, the system is still considered as inefficient. On average, you will be wasting about 3 gallons just to produce a gallon of purified water. That is why, some people still think that reverse osmosis water treatment is not really the best option to use in everyday life.


Some Types of Reverse Osmosis Water Filtration Systems


Whole House


There are several types of RO water filters, and the first one being the whole house reverse osmosis water filter. To make it easy to understand, the typical under sink reverse osmosis water system is installed under the kitchen sink. The water is treated for the purpose of drinking and cooking. Meanwhile, with the whole house filter, the system is installed at the main water line instead. The purpose is to provide clean water for the entire home to use, not just for cooking and drinking.


One example is the reverse osmosis shower filter used in the bathroom for bathing. Bottomline, the RO water can be accessed through every faucet at home, thus can be used for bathing, cleaning and doing laundry.


aq-4000w Aquasana Countertop FilterOther than the standard under sink RO water filter and the all-out whole house one, there is the countertop RO water system to suit your convenience. The traditional under sink counterpart requires detailed installation procedure, meanwhile, the countertop system can be put anywhere you want it to be.

The countertop reverse osmosis system is compact and can be used for traveling purpose. Some people may be more familiar with the name portable reverse osmosis water filter. You can carry the unit around and installed it easily where you need it.


Merlin RO Undersink Tankless Reverse Osmosis SystemAnother type of RO water filter is the tankless reverse osmosis system. This countertop utilizes a unit producing water directly into the container. If you have limited space to place the unit, this is your choice of RO water treatment. Moreover, if you hate to wait on clean water, this type of system is definitely right for you.

With this tankless RO system, the water is delivered at once and it can be delivered to multiple jugs or dispensers. Unfortunately, this tankless RO system is considered quite expensive if compared to other water filters.


That was a brief explanation regarding all you need to know about the reverse osmosis water filtration systems. Now you know what exactly reverse osmosis means and how it works in producing clean and fresh water. You now can think about the advantages and disadvantages that you will get when using an RO water system and drinking the RO water.

You also know the few types of RO filters that are sold in the market these days. Remember that reverse osmosis water is only one of different types of clean water you can drink from.



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