Comparing RO, UV, and UF Water Purifiers: What are the differences?

Choosing the right water purifier is crucial for ensuring healthy drinking water at home. Common water purifier technologies on the market include reverse osmosis (RO), ultraviolet (UV), and ultrafiltration (UF), each with its own unique characteristics and advantages.

What is an RO water purifier?

A RO (Reverse Osmosis) water purifier offers the highest filtration precision available. Its core is a reverse osmosis membrane with an extremely small pore size of just 0.0001 microns. It applies pressure to force water molecules through the membrane, trapping nearly all impurities, contaminants, bacteria, viruses, heavy metals, and even ions in the water and discharging them with the concentrated water. RO water purifiers effectively remove dissolved solids (TDS) from water, resulting in typically pure water.

What is a UV water purifier?

Ultraviolet (UV) water purifiers are primarily used for sterilization and disinfection. It doesn't involve physical filtration. Instead, it uses ultraviolet light of a specific wavelength (usually 254 nanometers) to destroy the DNA and RNA structures of microorganisms (such as bacteria, viruses, and parasites), rendering them unable to reproduce and achieving a sterilizing effect. UV water purifiers are often used as a supplement to other filtration systems because they cannot remove particulate matter, chemical contaminants, or heavy metals from the water.

What is a UF water purifier?

The core of a UF (ultrafiltration) water purifier is an ultrafiltration membrane with a pore size of approximately 0.01 microns. This membrane effectively removes large molecules and suspended solids such as bacteria, viruses, colloids, rust, and silt from the water, while retaining minerals and trace elements. Ultrafiltration water purifiers do not require electricity and do not produce wastewater. The resulting water is mineralized and has a better taste. However, they cannot remove small, soluble molecules such as heavy metal ions or some organic contaminants.


The Difference Between RO, UV and UF Water Purifiers

What are the differences between RO, UV, and UF water purifiers?

Which is better for TDS: RO, UV, or UF water purifiers? When it comes to removing TDS (total dissolved solids), RO water purifiers are the absolute top choice. TDS refers to the total amount of all dissolved inorganic and organic matter in water. RO water purifiers offer extremely high filtration precision, effectively removing most dissolved solids, including heavy metal ions, calcium and magnesium ions, reducing TDS to near-zero, resulting in pure water.

In contrast, neither UV nor UF water purifiers can remove TDS. UV water purifiers only sterilize and have no effect on dissolved solids in the water. While UF water purifiers can remove large-molecule impurities, they are unable to remove small molecules dissolved in water (such as ions), resulting in a relatively unchanged TDS value in the output water.

If you're concerned about the purity of your drinking water, especially if you want to remove heavy metals or TDS, RO water purifiers are the best choice. If you prioritize preserving minerals in your water and have a good source of water quality, ultrafiltration water purifiers are a good option. UV water purifiers, on the other hand, act more as an additional sterilization barrier to ensure drinking water safety. When choosing a water purifier, you should consider the water quality in your area and your personal needs.