Glass cutting DIY
I cut all my own tank holes with a diamond tip drill pice that i got from a glass shop that sells glass cutting tools, and i got a new drill low speed lots of talk and you have to run water throw the cutter when your drilling the hole my 25mm drill pice cost $140.00 Australian. just go and talk to a glass window repairman, they should be able to help you find same where to buy it over their and give you info too.