drilling an aquarium?

[Brhino]

I'm doing researching and planning for potential large freshwater corner aquarium. I will need an overflow (not an overflow box) so it can be flush or nearly flush against walls. I'm looking at the used tank market, but you won't always find a tank with an overflow. Has anyone ever tried or heard of someone drilling their own overflow holes in a glass aquarium? Offhand it sounds potentially disastrous to those without proper training and equipment, but maybe there's a way I don't know about.

[SunSchein89]

Definitely not unheard of. You just want to make sure the part you're drilling is not tempered, or the whole thing will spider web on you. Most bottoms of tanks are, especially the bigger ones. All you really need to do is: get a glass drilling bit (which are encrusted in diamonds, pretty cool huh?), keep a running water source over the spot you're drilling, and make sure you have some patience and a steady hand. If you can, practice on some spare pieces or maybe even buy a spare piece to practice on. Or if you don't want to go through all that, maybe ask some glass companies around you if they'll drill a hole for you. Make things a lot easier and I'm sure they couldn't charge you that much just to drill a hole.

[Brhino]

so... you can't drill tempered glass, most large aquarium bottoms are tempered, therefore you can't drill most large aquarium bottoms? Or did I misunderstand something?

[Northernguy]

If there is no stamp or sticker stating the glass is tempered,it does not mean it isn't tempered.The stickers do come off.Do not drill unless you are sure.
Most tank bottoms are tempered glass.I have no idea if yours is or not.Did you buy it new?
If you know the who the manufacturer is, call them and ask.

[Brhino]

I haven't bought anything, although I can confirm that one I'm looking at has a tempered bottom. I'm looking at people selling the tank used, so I'm wondering if I can consider the ones that are not drilled or not. Sounds like no, I need to hold out for pre-drilled ones.

[SunSchein89]

You could always drill the side just above the bottom piece. I don't think there would be many situations where you would need to completely drain the whole tank. Not sure if this would interfere with the placement of the tank or not, though.

[Brhino]

by my measurements, I'll have 3/4" between the back of the aquarium stand (which sticks out just a wee bit farther than the tank itself) and the wall. don't think that's enough space for a sideways access. Looks like it's pre-drilled for me!

[Cliff]

When I was looking into having a 55 galllon tank drilled, I was referred to two local glass shops to have it done by the professionals. I was told by a few people that have done this on similar and thinner glass that it is very easy to crack the glass if you don't know what you are doing and it gets easier to crack the glass the thicker the glass is.

It might be a good idea just to call around to a few glass shops and find out how much this would cost and who can do it for you. If you do end up getting a tank that needs holes drilled, you can just take it there on your way home and have it done. Very little risk.

I would also suggest that you get the bulk head flanges first so you can take them with you and have the glass shop ensure they drill a corrrectly sized hole.

I hope I'v helped