Actually the hotmelt glue worked fine. It seals the stem to the bowl, but on the outside. The bowl doesn't get hot enough to even soften it, but that might be because of our Canadian weather. Either way, I smoked it dry (without anything in the bowl) several times. No coughing, no smoke, no weird taste or smell or seizures. It could be because the water in the bong is catching all of that, I dont know, but it works great!