Best canister for low water level tank?

[Natalie]

Found it! http://www.monsterfishkeepers.com/forums/showthread.php?t=329022&highlight=stingray+river

Edit: Yeah you guys beat me to it! That is absolutely freaking-gorgeous! I am reading through it now to see more about the setup. I'll never get any productive work done tonight.

 

[Natalie]

One more question and then I'll quit. The tank I'm probably getting has an existing center overflow (not centered on the back wall but smack-dab in the center of the tank). I plan to saw off the overflow, but that leaves a drilled hole in the bottom acrylic panel of the tank. Can I just get a bulkhead with cap and seal it off? Or is it just too dangerous to leave a drilled hole in the bottom of a tank?