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 metals, 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 uses 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 includes the reverse osmosis membrane, which is the heart of the reverse osmosis water system. The RO membrane helps filter 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 the RO membrane from particulates that can clog the system. Then it goes to a carbon filter where the chlorine taste and odor are removed. Chlorine can damage the RO membrane.
Both sediment and carbon filters are pre-filters. They help extend the life of the RO membrane.
After the pre-filter, the water goes through a reverse osmosis membrane, which is the heart of the system. Incoming water pressure should be above 50 psi. If below 50 psi, the system will not remove contaminants effectively, leading to low water quality and rejecting more water to the drainage, resulting in high water bills.
To increase the pressure, you can decide to install a booster pump to increase the pressure. Increased pressure helps the system produce high-quality water, reduce water waste, and fill the tank.
To know the exact incoming water pressure on your membrane, you can install a pressure gauge before your RO membrane.
After the water passes through the semipermeable membrane, the 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 time 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 a long time 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 systems have an additional filter, such as a remineralization filter, that is installed after the 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 dispensed to the faucet.
Shop for RO system with UV light
Standard under sink RO system goes through the above stages.
How does the under sink Reverse 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, and the water is not stored in the storage tank, which 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 the video on how the tankless reverse osmosis water system works.
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| 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 the video to see how the countertop reverse osmosis water system works.
Shop for countertop RO system
