Best canister for low water level tank?

  • We are currently upgrading MFK. thanks! -neo
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?
 
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