drilling a hole... help!!

[mrcrane]

hi, i'm planning to add another canister filter to my 180g acrylic tank, for that
to happen, i need to drill a hole on top to put in the tubing. my question is..
is it safe to drill with the tank half full with water(or less).since i got fish in there. and also how far of a gap between the back to the hole? any info would be appreciated. thanks

 

[Clay]

Yeah, it's safe. You may want to do something about the plastic shavings that will end up in the tank though. You can place the hole anywhere you want.