Reverse Osmosis
A water filtration method that pushes water through a fine membrane to reduce dissolved minerals, metals, fluoride, PFAS, and many other contaminants.
Reverse osmosis, often shortened to RO, is a point-of-use filtration method usually installed under a kitchen sink. It uses water pressure to push tap water through a semi-permeable membrane.
Why it matters
RO is one of the most effective household options when you want to reduce dissolved substances that standard carbon filters do not handle well.
- Reduces total dissolved solids, hardness minerals, fluoride, PFAS, nitrate, and many metals
- Produces slower flow than simple carbon filtration
- Usually sends some water to waste during filtration
- Often includes a carbon pre-filter and post-filter for taste
When to consider it
Reverse osmosis is most useful in areas with high dissolved solids, very hard water, elevated nitrate, fluoride reduction goals, or specific contamination concerns. For chlorine taste alone, a carbon filter is usually simpler and cheaper.
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Disclaimer: Glossary definitions are provided for general educational purposes only and do not constitute medical advice or professional guidance. For specific health concerns about your drinking water, consult a qualified health professional. See our Terms of Use.