how to remove iron from hot tub water

Removing iron from hot tub water is essential to maintain water clarity and prevent staining of the tub’s surfaces and fixtures. Iron can enter your hot tub water from various sources, such as well water or corroded pipes. Here are steps to help you remove iron from your hot tub water:

Materials and chemicals you may need:

  1. Metal sequestrant or metal remover (available at pool and hot tub supply stores)
  2. Water test kit
  3. pH increaser (if needed)
  4. pH decreaser (if needed)
  5. Alkalinity increaser (if needed)
  6. Chlorine or bromine sanitizer
  7. Hot tub shock treatment


  1. Test Your Water:
    • Use a water test kit to check the iron levels in your hot tub water. Follow the manufacturer’s instructions to obtain accurate results.
  2. Adjust pH and Alkalinity (if needed):
    • Ensure that your hot tub’s pH and alkalinity levels are within the recommended range. Iron problems can worsen if the pH and alkalinity are not balanced. Use pH increaser or pH decreaser as necessary to achieve the appropriate levels.
  3. Add a Metal Sequestrant or Metal Remover:
    • Choose a metal sequestrant or metal remover product designed for hot tubs and follow the manufacturer’s instructions for dosing. These products work by binding to the iron ions in the water and rendering them harmless.
  4. Run the Hot Tub Circulation System:
    • Turn on the hot tub’s circulation system to ensure that the metal sequestrant is evenly distributed throughout the water. Allow the system to run for several hours.
  5. Retest the Water:
    • After the recommended waiting period specified by the metal sequestrant product, retest your hot tub water to confirm that the iron levels have been reduced to an acceptable range.
  6. Shock the Hot Tub:
    • To ensure that the hot tub water remains sanitized and free of contaminants, add an appropriate shock treatment product, such as chlorine or bromine shock, following the manufacturer’s instructions.
  7. Regular Maintenance:
    • Continue to monitor the iron levels in your hot tub water regularly. Depending on the severity of your iron problem, you may need to periodically add more metal sequestrant to prevent iron buildup.
  8. Prevent Future Iron Contamination:
    • To prevent iron from entering your hot tub water in the first place, consider the following preventive measures:
      • Use a pre-filter when filling your hot tub with water to remove iron and other impurities.
      • Regularly clean and maintain your hot tub’s filter to ensure it is effective in trapping iron particles.
      • Address any issues with your water source or plumbing that may be introducing iron into your hot tub.

Keep in mind that iron removal may take some time, and you may need to repeat the process if iron levels remain elevated. Regular water testing and maintenance are essential to ensure the continued clarity and quality of your hot tub water.

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