glass drill bits

[e46er]

hey
so i moved my 120 G tank last weekend and am sick of crappy POS submersible return pumps so ive decided im going to buy another snapper hybrid pump for a return pump and it will run my 2 reactors as well im going to plumb in a bypass as well it case the flow thru the tank is too much
but now i need to drill my sump i dont really like the idea of running the inlet piping over the side of sump as start up with no water in the pipe is going to be hard on the pump

1) how low to the bottom of the sump do you think i can drill ??? it will be an 1 1/2 bulkhead so i was thinking bottom of hole 2" up from the bottom glass

2) an 1 1/2" bulkhead requires a 2 1/2" hole does anyone have a diamond tip glass hole saw bit lying around they would be willing to lend/rent out?? beer cash??

[Cal_stir]

i put a 2 inch bulkhead 2 inches from the bottom of my 80 gal sump

[Myka]

I won't drill any closer to the edge than the size of the hole (not the size of the bulkhead) or 2", whichever is bigger. So if the hole is 1.75" I drill 2" away from the edge. If the hole is 2.5" I drill 2.5" away from the edge.

[rastaangel]

Industry standard is half diam. of hole from edge unless tempered. But for external pumps I usually go 2"+ from edge.
And FYI a tube bit with graphite will produce a much cleaner hole then a diamond embedded bit but will be harder to find and requires a tripod to drill

[monocus]

see how high your pump sits against your sump and drill accordingly.i can lend you a hole saw

[e46er]

Ok thats kinda what I was thinking for height good good

Monocus you have PM