@toni1132 I've been thinking more about the water pik and killing the MAC. Perhaps running saltwater through at the end and allowing it to sit in the plastic tubing would kill any potential MAC.?? I am attaching research that indicates that MAC cannot live in a saline solution of 7% or greater. (check the chart) I think I will start doing this. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4850692/ I was never sure if colloidal silver would kill it but feel good about the saltwater.