the picture attached depicts my fermentation bottle. I use 15 gallon surplus iodine barrels to brew 10 gallon batches, and they work pretty well.
looking at the picture, you can see the barrel has 2 threaded "bungs".
i use a large rubber stopper with a blowoff hose attached in the large bung.
Heres my problem. due to the rising gasses during fermentation, the rubber stopper always works loose (rises out of the hole), so the blow off tube no longer functions.i think it has to do with the threads in the opening
I am thinking a solution would be to drill a hole in the screw in cap, and inserting the blow off tube, then screwing in the cap.
My concern is having an explosion if the gasses get trapped.
Your thoughts ??