No one likes a dirty bong. Thankfully, a little patience, baking soda, vinegar, and hot water will solve this problem.
4 cups (about 1 liter) white or apple cider vinegar
2 cups (460 grams) baking soda, plus an additional ½ cup (115 grams) baking soda in reserve
19 ½-inch tall (50 centimeters) 40 quart/10 gallon (37.9 liters) stock pot
Bottle brush or toothbrush
Metal tongs with rubber pads
Place the bong into the stock pot. Pour in 1/2 cup (115 grams) baking soda down the bong stem. Pour the remaining 1 1/2 cups (345 grams) of baking soda into the bottom of the pot. Set the ½ cup baking soda in reserve to the side.
Slowly pour 1 cup (250 milliliters) of vinegar down the bong stem. This will cause an instant fizzy reaction creating carbonic acid. This will quickly dissipate into carbon dioxide gas and fizzle out.
Add the remaining vinegar to the pot. Let this sit for 5 minutes.
Add enough water to fully cover the bong. Bring to a boil then reduce to a simmer.
Watch the water level and do not let the bong become exposed to air, or else the bong will crack. Add more water if needed to keep it waterlogged.
Simmer the water for 1-2 hours, depending on resin buildup.
After the time is up, turn off the heat. Gently pull out the bong with the tongs and drain the liquid. Place onto a towel. Carefully pour the remaining reserve baking soda into the bong. Add a few tablespoons of the vinegar water to make a paste.
Gently scrub the inside of the bong with a bottle brush or toothbrush.
Rinse the bong out with warm tap water and place onto the second towel. Air dry fully before use.