Re: I need some help with airtightness
I prefer to use "friction tape" around the grommets on my hookahs. It is non-adhesive, there is no glue at all on the tape. You just cut a short length, usually less than one inch, and wrap it around the grommets. It makes an air-tight exclusive seal, and leaves no residue on the grommet, nor the glass. I found it at a hardware store.