Seems like there used to be 'bong cleaner' or something. some fluid... I don't have a bong anymore. Doesn't it seem like more bongs break when you're cleaning them then any other time? Lol.
Old thread I know, but I soak glass pipes in a jar of Purple Power for a few days, followed by a hot water rinse and air dry. If a stubborn resin deposit is present a pipe cleaner helps it along. The PP needs to be changed every 3-4 cycles but it really works great.
Me in my 20s = Clean my glass??? Me at 61 = I clean it after every use. Every... I like clean glass. Isopropyl alcohol does the trick.