A reverse osmosis water system is a water purification system that uses a semipermeable membrane to remove contaminants found in the water.
It uses water pressure to force water through a semipermeable membrane where contaminants are flushed into the drain and clean water passes through.
The process is capable of removing 99% of total dissolved solids contaminants in water including lead, fluoride, heavy metal, and chlorine.
How does the reverse osmosis water system work?
A standard under sink reverse osmosis water system involves different stages to filter out contaminants in the water. Each stage use a specific filter
The stages include
Stage 1: Include a sediment filter that helps to remove sand, silt, dirt, and rust. Sediment filter protect particulate from getting to the delicate RO membrane
Stage 2: include a carbon filter that helps remove chlorine, taste, and odor.
Stage 3: include reverse osmosis membrane which is the heart of the reverse osmosis water system. The RO membrane help filters out 99% of total dissolved solids (TDS) found in water. Such contaminants include lead, fluoride, pesticides, mercury, arsenic, hard water minerals, nitrate, and total dissolved solids. At this stage contaminants larger than 0.0001 microns are removed.
Stage 4: Include carbon post filter or polishing filter. It helps remove any remaining taste and odor in the water before the water gets to the faucet.
Water gets into the sediment filter and all particulates are removed. Sediment protects RO membrane from particulate that can clog the system. Then goes to carbon filter where chlorine taste and odor is removed. Chlorine can damage the RO membrane
Both sediment and carbon filter are pre-filter. They help extend the life of the RO membrane
After pre filter, the water goes through a Reverse osmosis membrane which is the heart of the system. RO membrane requires incoming water pressure above 50 psi. If below 50 psi the system will not remove contaminants effectively leading to low water quality and reject more water to the drainage leading to high water bills.
To increase the pressure you can decide to install a booster pump to increase pressure. Increased pressure helps the system produce high-quality water, reduce water waste and fill in the tank.
To know the exact incoming water pressure to your membrane you can install a pressure gauge before your RO membrane.
After the water passes through the semipermeable membrane purified water goes into a pre-pressurized storage tank where it is stored waiting for human consumption. Contaminants are flushed down the drain.
When you open the faucet the water pass through the final filter called the post/polish filter. The post-filter helps remove any taste and odor the water might have picked from the storage tank.
Why do you need a storage tank?
The reverse osmosis system treats water slowly. So the whole process takes a long before it produces purified water.
You need a storage tank that will collect purified water that is gradually treated. Without the tank, you can end up waiting for long to fill a glass of water or a pot when you open the kitchen faucet. The tank collects water so you can have immediate access to treated water.
Some system has additional filter such as remineralization filter that is installed after post filter. Ro membrane is known for stripping beneficial minerals that our body requires such as calcium and magnesium.
The remineralization stage help add those beneficial minerals.
Shop for RO system with remineralization
Other systems have an additional UV filter. A UV filter is the last stage where water runs in UV light before dispensing to the faucet. It helps eliminate bacteria, viruses, and protozoan cysts.
Also, a storage tank can be a breeding zone for bacteria and viruses. UV light is required to eliminate the bacteria, viruses, and algae before water dispense to the faucet.
Shop for RO system with UV light
Standard under sink RO system goes through the above stages.
HOW does under sinkREVERSE OSMOSIS Drinking Water System WORK?
There are modern types of reverse osmosis systems such as countertop and tankless reverse osmosis systems that work differently from under sink systems.
Both countertop and tankless reverse osmosis systems utilize 4 stages (Sediment filter, Pre-carbon plus filter, RO membrane filter, and Post carbon block filter) but they don’t have a tank where water is stored.
Water goes through 4 stages filter and is filtered faster not like the traditional RO system where the process takes longer. You get filter water right away from the faucet
Modern systems have a compact design that takes less space, water is not stored in the storage tank that poses a risk of secondary pollution, and requires no installation.
The drawback of the tankless and countertop RO system requires electricity to operate compared with traditional under sink RO system.
Watch video How does tankless reverse osmosis water system work?
Shop for tankless RO system
| Name | Image | Features | Where to buy | |
|---|---|---|---|---|
| 1 | Frizzlife RO Reverse Osmosis Water Filtration System – PD600-TAM3 |   | 3stages filtration Replacement filters Alkaline remineralization Brushed nickel faucet 1.5: 1 drain ratio 600 GPD Smart LED Display | Buy now Frizzlife Buy now Amazon |
| 2 | Brondell Circle Reverse Osmosis System |   | 4-stage 400 GPD Fast Flow Faucet with LED filter change indicator 2:1 Drain Ratio | Buy now Amazon |
| 3 | Waterdrop G2 RO Reverse Osmosis Water Filtration System WD-G2-W |   | NSF Certified TDS Reduction 400 GPD Fast Flow Ordinary Faucet 1:1 Drain Ratio | Buy from Water drop filter Buy now Amazon |
| 4 | SimPure RO Reverse Osmosis Water Filtration System |   | 4stages filtration Replacement filters NSF certified Smart faucet 1.5: 1 drain ratio 400 GPD | Buy now Amazon |
| 5 | Frizzlife RO Reverse Osmosis Water Filtration System PD600 |   | 3stages filtration Replacement filters Brushed nickel faucet 1.5: 1 drain ratio 600 GPD Smart LED Display | Buy now Frizzlife Buy now Amazon |
| 6 | Oasis osmosis home RO Reverse Osmosis Water Filtration System |   | 3stages filtration Replacement filters Faucet 1.5: 1 drain ratio 600 GPD | Buy now Amazon |
| 7 | iSpring RO500 Tankless RO Reverse Osmosis Water Filtration System |   | Twist and Lock Filters Smart TDS Monitoring Faucet 500 GPD flow rate 3stages filtration Replacement filters 2: 1 drain ratio 600 GPD | Buy now Amazon |
| 8 | GreatWell ROG400 Tankless Reverse Osmosis Water Filtration System |   | Twist and Lock Filters RO Faucet 400 GPD flow rate 3stages filtration Replacement filters 1.5: 1 drain ratio Built-in true filter change indicator | Buy now Amazon |
| 9 | KFLOW Reverse Osmosis Water Filtration System |   | 5 stages filtration Replacement filters RO faucet 2: 1 drain ratio 400 GPD Smart LED Display | Buy now Amazon |
| 10 | Brio Reverse Osmosis Water Filtration System |   | 00 GPD Fast Flow 2:1 Pure to Drain - TDS Meter Smart Faucet Filter life indicator Provide two types of water filtered and purified 5 filter combined in two cartridges (sediment filter, GAC filter, RO membrane, carbon filter, sediment filter) | Buy now Amazon |
Watch video How does countertop reverse osmosis water system work?
Shop for countertop RO system
