Mine also goes pink. I thought it was from my make up 😂😂

Do you change your tubing out regularly? I've never had this happen with my O2 tubing, but we grow pink mold sometimes in showers and other places that don't get completely dry. That would not be good in O2 tubing!

i think sometimes it is the brand of canula you use...the others I switched from because of that and the nasal prongs were too long! Try looking into a brand change!?

mine has never done that but I change it once a month.

Some of mine start turning shortly after I start using them. Either way, I change them every two weeks as the provider recommends. The fifty foot tube gets changed monthly.