# 3 inch hole in bottom of 20 gal tank?



## Edwii (Jan 1, 2012)

Hello, I have a 20 gal tank I have narrowed it down to only needed a single 3" hole in the center of the bottom of the tank for the bulkhead fitting i wish to use. I plan on resting the bottom of the tank on a solid wooden base to spread out any pressure and for added support. The glass is about 5mm its 30x12x13 ; Can some one give me an opinion or two if the 3" hole will weaken the glass too much?


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## Edwii (Jan 1, 2012)

Second question: 
What is the smallest size i can get a 1.5" bulkhead (outer diameter mounting hole size)? My current bulkhead has a 3" Outer Diameter, smaller would be better like 2.5 or better, it would also help to know where to get it?


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## Yan7gin (Oct 7, 2011)

Well normally if you have 1.5 " bulkhead, you go 1/2" bigger, so i would drill 2" hold. And on the bottom of the 20 gal???? For my part, i will not do it. All the weight is sit on the bottom so i don't think is a good idea but maybe you can do it without any problem! For myself i did drill 1.5" hold on the back top side of a 20 gal but never on the bottom i found the glass to thin for a hold thats side


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## jkcichlid (Apr 21, 2010)

Can't answer your first question but to find a bulkhead in Chwk, go to Southern Drip Irrigation. They are on Yale Rd west just east of Lickman road


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## abel (Apr 21, 2010)

most tanks have a tempered glass bottom that will shatter if you try to drill it


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## mikebike (Sep 8, 2010)

I have a 20 gallon with a bulkhead fitting for sump in one corner availible for $25
Call me if interested


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## gklaw (May 31, 2010)

abel said:


> most tanks have a tempered glass bottom that will shatter if you try to drill it


Mostly for large tanks only. The small pane on smaller tanks does not need tempered


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## Yan7gin (Oct 7, 2011)

I did drill the bottom of my 135 gal and my 90 gal without any problem. I found the thicker glass more easy to drill than thiner glass. Just take time with lots of water when you drill and no big pressure on your drill and remove all pressure at the end to make sure to not chip the glass


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