What are the dimensions on the tank? It doesn't look like a 220 since it's wider than it is tall.
Holy hell! I drilled a 3" hole through glass. It took over an hour and the bit was worn out when I was done.
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[/URL]I find thick glass easier to drill than thin, less chance if cracking.
if you make a template, and use a diamond coated hole saw drill bit, with lots of water, and it only takes a few moments.
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