Weird fungus
 

Just checked my spare wheel and found this ..... TROC about a year old. Any ideas ? Wondered if it has anything to do with ad blue?
https://cimg7.ibsrv.net/gimg/volkswa...6fa7d6a54.jpeg

https://cimg9.ibsrv.net/gimg/volkswa...fa8638298.jpeg
https://cimg0.ibsrv.net/gimg/volkswa...65a793235.jpeg

Welcome to the forum. https://i.ibb.co/KLf4Dsb/VWwelcome.gif

Its nice to see you made an intro on your own. ;)

That isn't an easy question to answer on a forum.

You will get fungus if its damp or you have a water ingress in the boot.

Please tell us your car spec in your signature

Post approved.