Pink mildew on white garage door?

I have seen two white garage doors that have pink on them (maybe mildew like grows in a shower), but I couldn’t get it off. I assumed that SH would work, but I went from downstreaming 1% with elemonator up to using a 12 volt at 5% with elemonator. Neither one made an impact. The pink seems to be most present on the lower horizontal part of the insets. Any ideas? Sorry I don’t have a picture.

Pictures. We need pictures.


Ok. I don’t have any. Thank you for trying. Perhaps there is someone here from Central Florida or a location with similar climate who has seen what I am describing.

Well, if it’s living the SH would have killed it. Gotta be something else.

If it’s pink like the buildup in your shower, that’s bacteria. If that’s the case, SH should kill it. It’s not that hard to clean from a shower, so this should come off easy too if that is what it is

We turned a white stucco house pink last year - the only reasonable explanation we could come up with was that the salt was reacting with iron minerals in the stucco/paint/pigment

Thanks everyone for your input.