As said before you are OVER THINKING THIS.
The chimney is not air tight and it doesn't have to be. As long as there is equal pressure in the tank and the chimney no liquid can flow from the tank into the chimney because to do so air would need to replace the liquid.
The chimney isn't sealed on the bottom either and there are juice channels cut into the base. If liquid was to flow into the chimney it would certainly take the path of lease resistance, IE the juice channels, and not through the slight if any gap where the 2 chimney parts meet and around, through all the threads of those 2 parts.
Not sure why you keep posting the same thing when it has been explained to you many time already.
If you don't like the Kayfun then find some other tank system yo use.
The chimney is not air tight and it doesn't have to be. As long as there is equal pressure in the tank and the chimney no liquid can flow from the tank into the chimney because to do so air would need to replace the liquid.
The chimney isn't sealed on the bottom either and there are juice channels cut into the base. If liquid was to flow into the chimney it would certainly take the path of lease resistance, IE the juice channels, and not through the slight if any gap where the 2 chimney parts meet and around, through all the threads of those 2 parts.
Not sure why you keep posting the same thing when it has been explained to you many time already.
If you don't like the Kayfun then find some other tank system yo use.