Q: How do I store my RO membrane when it's not being used?

A: The manufacturer recommends soaking membranes in a 1% sodium metabisulfite (SMBS) solution for an hour before packaging for up to three months. Here are the steps:



Preservation Process


1. Prepare a 1% sodium metabisulfite (SMBS) solution:

  • Use food-grade SMBS (not cobalt-activated)
  • Dissolve in high-quality water (ideally RO permeate or filtered freshwater)

2. Remove the membrane element from the pressure vessel


3. Soak the membrane:

  • Immerse the element in the SMBS solution for 1 hour
  • Position the element vertically to allow trapped air to escape
  • Ensure complete coverage of the membrane


4.After soaking:

  • Remove the element and allow it to drip dry (do not rinse)
  • Element should remain moist but not dripping wet


5. Packaging:

  • Seal the element in an oxygen barrier plastic bag
  • The original packaging bag works well if available
  • Do not add extra solution to the bag as the moisture in the element is sufficient
  • Ensure the bag is completely sealed to prevent air entry


6. Storage

  • Store out of direct sunlight in a cool area and keep from freezing
  • Label with the date of preservation and check every three months and replace cloudy solution or solution that drops below pH 3