hmm...$15 dollars for each hole...$1200+ for a new tank if it cracks. It seems like a no brainer to me. I have never drilled a tank, but I did work with stained glass some years ago, and the tool you are talking about sounds like a glass scorer...not a glass cutter. What is does is score, or cut a groove, in the glass, and by tapping the glass after you score it you are making a controlled break along the score. Considering that about 10% of the time I tapped the glass, the whole piece broke, I would never
recommend using it on such an expensive tank. IMO
, if you spent the money on the tank, you should spend the money on a professional to cut your holes. I really don't mean to sound harsh, I just would really hate for your next post to be about how the tank cracked.