yeah man the purpose of the salt is to act as an abrasive so the bigger the better. So yeah kosher salt or epsom salts are perfect... you can also use rice but its a pain to rinse out. just make sure you rinse well after epsom salt.
i use sea salt (with no iodine added) the sea salt is large chunkness, which grinds off that nastyness. the no iodine added helps keep your glass clear. i prefer 99% alcohol.
k i just cleaned my bong for the first time i learned sum things... Rubbing alchohol 91% with epsom salt breaks thru ziplocks( it ws a think one too) =[ andd i have percs and chambers in my bong..the large salt chunks dont go down there...
I would personally i get a wine stopper(the thing for the bottle) to block off an 18mm joint, and a cut cork or glass stopper for a 14.5mm joint. Fill it with grunge off and let it sit for 12 or so hours, and then pour the grunge off back in the bottle for the next cleaning.
Some people say to use rice, but in my experience rice is a huge pain in the ass. You have to rinse like 20 times to get all the rice out. And the rice gets soggy so it doesnt act as an abrasive as well.
Use 91% iso with a few drops of liquid joy & epson salt no baggies for bongs put the epson salt into the pipe add the iso make it like a thick mud shake and rotate the pipe use bottle brushes when you can...rinse with hot water to disolve the left over salt the joy makes the glass shine..
i use iso and regular table salt. works perfect, and it only costs like 50 cents for a thing of salt that lasts me for quite a while