So I just got my new bong, the down stem it came with was made with pooooor quality. I'll show you what I mean and if I can fix it? Tried to get the best picture possible but taking a pic directly down the tube makes a weird light effect. It also has some bubbles on the end
If you can see it the end is like a half circle lol. Instead of a completely around end. +REP for some good answers.
id just leave it or buy a new one. it would be pretty hard to open the end of that up without breaking it. EDIT: dremel tool could possibly work to open the end up.