The Purge
The purge is something that seems to often be looked over when checking your hookah, but it's important to remember that it's still a place that can provide leaks as far as airflow is concerned. Generally I recommend swapping out any metal purge balls with a small plastic BB, so that it'll never rust. Keep your purge clean, so that you'll never have a stuck purge (not a fun thing to fix mid-session). If you feel like your purge ball is getting stuck too frequently, you can actually coat it with some olive oil, which should lubricate it enough to where it won't get stuck much at all. If you think your purge is having a leak, the easiest way to check is to fill your base up with water, place the hookah on the base, cover the bowl port with your thumb, then directly inhale from the hose port. If you get any airflow, you have a leak in your purge. Fixing it can be as easy as swapping your purge ball out with a bigger one, or as complicated as fixing a weld issue (JB weld is your best friend in this case).
The Hose Port and Hose
The next part we're going to be looking at is the hose, and hose port. This is probably the next biggest spot where stuff can go wrong, after the bowl itself. So for the hose itself, the best way to check for leaks is to take the hose out alone, then cover the port with your thumb and just pull like your normally would. If there aren't any leaks, you shouldn't be able to pull at all. If there are, you'll get mild airflow, but it shouldn't be anything insane, so long as your hose doesn't have a giant gash in it (which I would hope you would notice). If you do feel slight airflow, the best way to find out the specific spot your hole is to cover the hose with soapy water, then do the same practice as before. You should notice bubbles coming off of the area in which your leak is. From there, usually duct tape is your safest bet for plugging the hole. In some cases, with cheap hoses like a NuHose or Fancy hose, it's better to just snag another hose than to plug it, if they're cheap enough. If your hose is good, it's time to check the hose port. What I'll usually do is take the stem naked, then try to plug the hose port on the bottom of the stem (where it would normally enter the base), and try to pull from the hose port directly. Same deal as before - if you have no airflow whatsoever, you're golden. If you do have airflow, check to see if you need to weld the hose port. If you have to weld, JB weld is going to be your safest bet here.
Water Level
This is something that gets debated a lot as to what's right and wrong, but, as most things are with hookah, it all boils down to personal preference. Generally speaking, your water level should be about an inch or so above the bottom of your stem. If you feel like it's hitting too airy, you can add extra water. If it's too restricted, try going with less water. You want at least half an inch of coverage, otherwise when the water bubbles from smoking, it can leave the bottom of the stem exposed, which is something you generally want to avoid. That said, the water is in the base for a reason - unfiltered hookah smoke is not a very pleasant experience.
We good now?
All in all, this should cover most of the major flaws that can go wrong when smoking. Have you tried any of these fixes before? How did they work for you? Are there any we missed? Let us know in the comments below! Hopefully this helps you fix your sessions, if you're having these kind of issues. As always guys and gals, thanks for reading, and happy smokes!