Drilling Glass for BA Overflow


New member
Hi guys,
I am 15 years old, and I really want a sump. The only thing holding me back is the tank drill. I have seen countless youtube vids on it, but am worried about cracking the tank. Any suggestions? (An lfs told me they would for 75$, and I said shove it)


New member
Grab your parents and drill it. You need a jig or something to hold the drill in place while you start, a constant stream of water, time, and a steady hand.

Make sure you read the Bean Animal silent overflow thread until you have a good idea on how to set it up.

Good luck and Enjoy


Team RC
$75 isn't too bad, by the time you consider the cost of the bits and the jig you'll probably be close to that.

+100 to having everything planned out ahead of time. Nothing sucks more than realizing you drilled your holes in the wrong place!


New member
I drilled mine for $4 (cost of the bit online). Steady hand and very slow with a squirt bottle to irrigate it. No chips or issues at all.


New member
If I can do it, I believe I can do it! Or some such... :)


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New member
Use a jig.

Use a jig.

First put masking tape over where the holes will be on the back of the tank. Draw the holes where you want them/ where they ought to be. Drill a hole slightly larger than your glass cutting bit in a 2x4, and if the bit doesn't quite fit just sand it out a bit until it does. Clamp this 2x4 "jig" over the first hole and fill it with water. Slowly grind the top layer of the glass until there is a slight grove that the bit will sit in, then you can ramp up the speed. Remember keep water on the cut and just let bit and the weight of the drill do the cutting. You do not need to apply extra pressure.

Check out my build thread. http://www.reefcentral.com/forums/showthread.php?t=2472350


New member
When you start out put some plumbers puddy around the intended hole and fill with water which will keep your bit cool. Make sure your glass is not tempered!! That will make for a bad day. Otherwise its really simple take it nice and slow usually about 2 minutes or so. Good luck!