10g overflow or drill?

[drillsar]

I want to add a 5g sump to my 10 gallon tank. I heard 10 gallons can't be drilled is that true? if not what kind of overflow? I was looking into a herby drain.

 

[mcgyvr]

All depends on who made the tank and if its tempered glass or not.. There are videos on youtube showing how to identify with polarized glasses,etc...

you could also just do a HOB overflow and not drill at all..
Herbie is fine if you drill..