Drilling two holes in 5mm glass?

Question

I want to drill two holes next to each other through a 5 mm glass. It's a fish tank and I want to create an overflow/sump by drilling the bottom pane glass with a 1 3/4" & 1 1/4" holes. What I want to know is what the safe distance(considering engineering) can the hole be drilled from the edge of the 24"x14" glass and how far the spacing needs to be from each hole. I don't want the glass to crack.

THanks

Answer 1

I would take it too a specialist  as I don't think it can be done,

Answer 2

I agree with him -definitely take it to someone...glass can be very tricky to drill through!

Answer 3

drilling through glass requires a special drill bit.  take your tank to a glass cutting company and they will do it for you.  i wouldn't think it would cost a fortune either.