I use bongs with a very thin layer of water at the bottom, to add moisture. Not enough to cover any of the percolator tubes. It gives smooth vapor without losing taste and I can use the piece for weeks before It needs a clean. And when I clean, I usually scrape the oil and revape it. The best of both worlds
Sry for sticking my nose into your business,but from biological
point of view,it is not a good idea to leave any ammount of water even for 24h. Buy i am pretty much probably worry too much about his kind of things so,so they might seem very important to me than they are in reality.I clean with hot water and soap before every session.If am going to store the wp i pour all the water i put a small ammout of alcohol in it and plug the holes.Works both for desinfection and prefention. I imagine you can reuse the same alcohol if you pour in a washed WP every time.
I am getting the impression for people using dry pieces thinking they dont need to clean them regularly that since they dont have water to host the bacteria and what about the area where the mouth meets the glass and the things that are flying all over it if/when you cough ? It is a pretty good place to breed bacteria. I admit that the taste is slightly muted but also things that spoil it are greatly reduced,so i take is a more refined,not weaker.
Drinking glasses are cleaned daily and more often after every use ,i dont see why hygene protocol should be different for any other glass vessel.When your mouth contacts the glass it leaves biofilm,that hosts bacteria,i cannot imagine putting my lips at the same place for 7 days without cleaning it.
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Now i realise i am too baked and might have taken your words wrong,thinking you dont clean it at all for 7 days. Maybe by cleaning you mean "complete cleaning" with alcohol,salt,etc.. ,to get rid of the gunk.