thats a video of me drilling it. Its just shy of 6 minutes long. I used a Diamond bit Hole saw from www.glass-holes.com to drill it. If I remember correctly the Diamond bit I used for this was 1 3/4" because the bulkhead is a 1" bulkhead. I will most likely be doing a 3/4" flex tubing upto the tank and well you need a bigger drain than your inlet is :d. The bottom pane isnt tempered so if you plan on ever drilling a tank you need to make sure the bottom pane isnt tempered (or whatever pane you drill). I just guess that this one isnt tempered because I have never seen a 29g tank with a tempered bottom and it wasnt tempered . You will know its tempered because it will shatter once you hit the plastic point. I have drilled my saltwater aquarium for an overflow and returns so I drilled 3 holes in the back pane on my 29g saltwater aquarium.