Should you put Alcohol in a Bong?

To put it bluntly, using alcohol in a bong when smoking weed is dangerous. One of the reasons we drink alcohol instead of inhaling its fumes via some device is because doing the latter is not enjoyable and will make you very sick. 

The way your body processes substances depends on how they are consumed. For example, with cannabis edibles, the THC is processed in your stomach and liver, so it takes a while for the THC to kick in. When smoking or vaping weed, however, you'll feel the effects much faster because the THC is absorbed directly into the bloodstream via your lungs.

With alcohol, the stomach and liver must process the liquid before you feel the effects. Therefore, inhaling alcohol fumes will hit you much faster as it is absorbed through your lungs.

Using alcohol instead of water in a bong will also compound the fumes. You are displacing what would typically be water vapour, or standard ambient atmosphere, in the bubble or on the smoke, with fumes of the alcohol, which then cause intoxication. So every time you pull a hit, you will not only be getting the smoke of the cannabis but also be getting the alcohol fumes.

Another problem with inhaling alcohol is how you quantify a "hit" of alcohol vapour. If you inhale alcohol fumes, the problem is that you can't measure how much you are taking in, so how do you limit it, so you don't take too much?

The bottom line is that repeatedly inhaling alcohol, in general, is dangerous. Short-term common side effects include dizziness, headache, inability to move around and poor muscle control.

If you've ever been "crossfaded" from mixing drinking alcohol and smoking weed, you will know it's a tricky line to walk; get it wrong and quickly ruin your night. 

Crossfading is even trickier to control when you're not just mixing alcohol with weed but inhaling alcohol with weed. So ultimately, it's firmly recommended that you not put alcohol in your bong. It isdangerous and it will make crossfading more difficult to gauge. Additionally, it'll kill the taste of your weed and lessen the high, and no one wants that.