Reverse osmosis systems are one of the most common and effective water treatment technologies. They work by removing contaminants from water through a process of pressure and filtration. A reverse osmosis system is a water purification system that uses a semipermeable membrane to remove ions, molecules, and larger particles from your entire home or at the point of use. In this section, we will be discussing how to choose the right reverse osmosis system for your needs.

What is the reverse osmosis water system?
Reverse osmosis is a water purification method that uses a semipermeable membrane to remove water contaminants such as heavy metals, dead bacteria, dissolved impurities, and large particles. In short, it is called RO.
Read our article on how a reverse osmosis water system works.
How to Choose Reverse Osmosis System
Size
The first thing that you need to consider is the size of the system. This is because not all systems are created equal and some may be too small or large for your needs. If you have a large family or live in a larger home, then you will want to buy a larger system with more gallons per day. For a large family, a whole house reverse osmosis or under-sink reverse osmosis will fit. For smaller families, a small system such as a Tankless RO system will suffice. For apartments or offices, a system such as a countertop RO system will suffice.
Installation point
Another thing that you need to consider is where you plan on installing it. The reverse osmosis system is installed at the point of home entry or the point of use.
The point of entry means the system will treat all the water that enters your home. Every faucet in your house will get non-contaminated water. Be it water for cleaning, drinking, cooking, showering, or water used to flush the toilet.
It guarantees your entire house is free from any traces of organic or inorganic contaminants.
Below is the comparison table of the best point of entry reverse osmosis system and you can read a review of some of the best whole house reverse osmosis systems.
The point-of-use means the system will provide purified water only at the location where it is installed.
The best point-of-use reverse osmosis systems include
The contaminant that the system removes
The method involves a number of filtration stages. Each stage removes a specific contaminant from the water. Most reverse osmosis systems come in four, five, or six stages.
Stages of the whole house reverse osmosis system
Most Ro water system involves five stages of filtering
- Sediment Filter: Removes fine and large particles such as sand, silt, and dirt. It also prevents sediment from going through the reverse osmosis membrane, which is damaged by sediments.
- Carbon filter: it consists of an activated carbon filter and a granular activated carbon filter. Both help to remove unnatural tastes, chlorine, odor, suspended particles, organic particles, and other chemicals that can be found in the public water supply.
- Reverse Osmosis Membrane: It’s the main component that removes bacteria, viruses, pesticides, chemicals, and other dissolved impurities.
- Polishing filter: This is the final stage or final filter that stabilizes the water’s taste quality and removes any traces of bad odor.
Extra stages
Stage 6: Alkaline filter: There are important minerals that are removed by the reverse osmosis membrane. At this stage, you can add those important minerals and alkalize the water, or adjust the PH using calcium and magnesium. This stage is called “remineralization” or “alkaline filter.”
Stage 7: Use the UV filter to kill the microorganism.
What impurities does the whole house Reverse Osmosis system remove?
A reverse osmosis water system operates in five stages, and each stage is meant to remove a particular contaminant.
The sediment filter is meant to remove sand, silt, and large particles. removes impurities of 0.001 microns.
The carbon filter is best for removing chlorine, bad taste, and odor.
The reverse osmosis membrane, which is the heart of the system, removes a wide variety of contaminants such as sodium (salt), sulfate, calcium, potassium, nitrate, iron, zinc, mercury, selenium, phosphate, lead, arsenic, magnesium, nickel, fluoride, manganese, cadmium, barium, cyanide, and chloride.
Read more about the percentage of RO membrane removes
It is significantly used to purify water from lakes, rivers, and tap water (public water supply).
Types of reverse osmosis systems
There are different types of reverse osmosis systems: under-sink RO systems, tankless, countertops, and systems with alkaline filters.
Under-sink and whole-house reverse osmosis systems are commonly known as conventional units. They use the old method of filtration where a storage tank is required. The under-sink is installed under the kitchen sink and provides purified water at a single faucet on the sink top. The whole house RO systems are installed at the house’s main water entry. It treats all water that enters your house.
Countertop and tankless are known as compact units. They use small spaces in your house with minimal installation. They require no storage tank compared with conventional systems.
The reverse osmosis system with an alkaline filter has an added remineralizing filter that helps increase the pH level of your water and restore those healthy minerals. The system also has other stages of filter that help remove contaminants in the water.
What happens to the water that has a contaminant?
One of the disadvantages of an RO system is the amount of water wasted in the process.
The domestic RO system uses four gallons of contaminated water to produce one gallon of filtered water.
Three gallons go to waste, but you can reduce this by adding a booster pump to reduce water wastage.
Some systems, like the Home Master TMHP HydroPerfection Under Sink RO System, come with a pump.
The Home Master TMHP HydroPerfection Under Sink RO System reduces the amount of water wastage to one gallon for every gallon produced.
Other systems have advanced technology like Brondell H2O+ Circle Water Saving that reduces the amount of two gallons for every pure water produced.
All the same, there is the volume of water that will be wasted which is a concern for every person.
In the system, there is a drainpipe or waste pipe. You can connect your waste pipe to the normal faucet or have a collection point and use that water for cleaning, flushing toilets, or watering crops.
Is a whole house reverse osmosis system necessary?
A whole house reverse osmosis system is necessary where water quality is severe. For instance, well water has a presence of severe contaminants but municipal tap water is already treated you do not need a whole-house system.
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