[Easy7]

Only thing that cleaned my coffee cup was strait bleach. Tried bar keepers friend, a toothbrush and all sorts of options. Only thing that worked was bleach.

Bronners always worked for me. Maybe not legal clean like bleach would. When I would travel I would clean my glass pipe. Smoke blunta or joints on the highway and only smoke bowls at camp or hotel. Gotta be careful in the bible banging states like Utah and Idaho.