Only use the following types of water:
- Distilled or sterile bottled water
- Boiled for 3-5 minutes (then cooled)
- Microfiltered to 0.2 microns
Here are published recommendations from the US FDA regarding water used for nasal irrigation: https://www.fda.gov/consumers/consumer-updates/rinsing-your-sinuses-neti-pots-safe
New User Water Tip
Most users prefer to warm their water prior to use. If you do this, do not overheat the water. It should be lukewarm to the touch and not hotter than about 85°– 90°F (29°– 32°C).
WARNING: DO NOT USE TAP WATER UNLESS STERILIZED BY BOILING FOR 3-5 MINUTES