dilute the rubbing alcohol with water warm cold or whatever and just swish it around the bong...then empty it out wipe it down with whatever you can (they have brushes at head shops)

Then put the icecubes in the bong and put the warm (and I mean close to HOT WARM but not too hott you don't want to crack your bong) and let it sit until the ice melts and then drain it out again .. scrub it.. rinse it SEVERAL times with warm water alone then scrub it one more time..

COPY REPEAT IF THE SCENT STAYS AROUND