Drilling Glass to Make an Overflow

[acurro]

I have recently found an inexpensive 220 gallon aquarium that comes with the stand I want, but it was originally a freshwater set-up and needs to have the glass drilled to make an overflow. Has anyone drilled glass before? Can I drill a side of the tank near the bottom to make an overflow, or could I drill near the top of the tank?

[30mini]

You need to make sure that it is not tempered before you try and drill it. It is possible to do it, and has been done many times before. Search for the Calfo Style overflows, that is what you will want. If you can make it a coast to caost one, that will be even better

[adnup]

I drilled my own, you can see <a href="http://www.reefcentral.com/forums/showthread.php?s=&threadid=831994" target="_blank">HERE</a>. There are links in that thread.

[acurro]

I have read Calfo's book (and actually heard him speak two weeks ago! he is great), and I would love to do a calfo-style overflow, it was my original plan with this tank, but where does one buy the box itself? Also, is drilling multiple holes in the back of the tank dangerous to the stability of the tank.

[30mini]

Why buy the box when you can get glass cut at Lowes or HD. Just get some 1/4" glass, get them cut it to size, and silicone it in. Bam... your done! Drilling multiple holes is fine, just don't go overkill and make sure they are far enough away from each other

[Jeremy Blaze]

Have a look here,

http://www.reefcentral.com/forums/showthread.php?s=&threadid=473152

and here
http://www.reefcentral.com/forums/showthread.php?s=&threadid=814800

[Fiziksgeek]

Its already been said, but make sure its not tempered or this will happen:

http://reefcentral.com/gallery/data/500/9619910.JPG

[h20cooled]

I've drilled probably 20+ holes in glass tanks without a single one breaking, I made sure none of them were tempered before I drilled though. You can get diamond hole saws from eBay for cheap if you look around.