Well Water Interpreter

Private well answer guide

Reverse Osmosis for Well Water: What Does It Remove?

Reverse osmosis can reduce nitrate, arsenic, lead, uranium, sodium, TDS, and many PFAS compounds at a drinking water tap, but it does not disinfect a contaminated well or solve whole-house odor and staining.

Search: reverse osmosis for well water what does it removeUrgency: Routine

What to test

  • Nitrate
  • Arsenic
  • Lead
  • PFAS
  • TDS
  • Hardness
  • Iron

What to do next

  • Test the raw water first so the RO system is designed for actual contaminants.
  • Pretreat iron, manganese, hardness, or sediment if they can foul the membrane.
  • Replace filters and membranes on schedule.
  • Verify removal with post-treatment lab testing for the target contaminant.

Common questions

Does RO remove bacteria?

RO is not a substitute for well disinfection or source correction when bacteria are present.

Is RO whole house or under sink?

Most residential RO systems are point-of-use under-sink systems for drinking and cooking water.

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Keep your well history

Interpret once on the web. Track forever in the app.

Save test history, set annual reminders, compare results over time, and create a shareable report for your family or water professional.

Save this result in the iOS app