I will be drilling a 20 gallon high for a fuge, hopefully this week for reference pics, but for now, it will be mostly just words 
. I have drilled a couple tanks, and find it to be quite easy. I take a cordless or corded drill (after marking the location of the hole) and put the bit in. With a hose moving water across the glass, I start the hole at a 45 degree angle, and slowely move toward a 90 degree angle, allowing for the bit to cut a groove. Once the bit is at a 90 degree angle, I put no pressure on the bit, and go about half speed until I can see water dripping through the glass. I then slow down to avoid a messy hole, and keep going until the piece of glass dops onto a towel below. That is about it, just remember, do NOT put pressure on the drill, and keep in mind, petco is running the dollar a gallon sale, so try a 10 gallon tank to start, so if you mess up, it is only 10 bucks, not the big tank, or more expensive one you want to drill
. I have drilled a couple tanks, and find it to be quite easy. I take a cordless or corded drill (after marking the location of the hole) and put the bit in. With a hose moving water across the glass, I start the hole at a 45 degree angle, and slowely move toward a 90 degree angle, allowing for the bit to cut a groove. Once the bit is at a 90 degree angle, I put no pressure on the bit, and go about half speed until I can see water dripping through the glass. I then slow down to avoid a messy hole, and keep going until the piece of glass dops onto a towel below. That is about it, just remember, do NOT put pressure on the drill, and keep in mind, petco is running the dollar a gallon sale, so try a 10 gallon tank to start, so if you mess up, it is only 10 bucks, not the big tank, or more expensive one you want to drill 
