Bong water
Used bong water is a notoriously disgusting fluid. In many movies and even in company of others stories are told of bong water's ability to stain anything and make it smell awful. Bong water ranges from clear when it is fresh, to a slightly used green, yellow or brown tint, which will get worse as the water is used more. A practice of some bong users is to turn the bowl around backwards and suck the remaining ash and unburned material down the stem into the water when the bowl is empty. While this is convenient it rapidly degrades the quality of the bong water. If this is done bong water can go from dark green or grey, to black, and will usually have chunks of dark unburned material floating around. As the quality of the water degrades so does the taste of the smoke. Over a long enough time the bong will develop a distinct unpleasant odor and the smoke drawn through it will acquire that taste as well. Bong water is extremely unpleasant to ingest. Drinking bong water will produce minimal psychoactive effect, since THC and other cannabinoids are minimally soluble in water.

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