Plastic tanks

[GaryE]

Brilliant. That I will do.

It can be very cold here, so as long as guys don't dance close to the fire, there's little for Tik Tok. We don't like sacrificing animals, but the neighbours are always out there dancing around while burning paper rams, cardboard first born sons and other biblical sacrifice origami creatures. We have a lot of paper products here.

I know it would be good to invest in proper equipment, but I figure I won't be drilling tanks often. These older but solid 5 gallons should mostly make it through, and it's going to be a Spring project when I can work outdoors. No sumps or central filtration - purely simplified water changing. I have a dozen 5.5 gallons, and if 9 make it through, I'll be rich.

 

[Magnum Man]

so, you can't drill tempered glass, only non tempered, and of coarse there are specialty drill bits for glass,

9 Piece Premium Diamond Bit Set - Multi-Tool for Precision Drilling Porcelain, Ceramic, Glass, Marble (Blue, 9 Pcs) - Amazon.com

9 Piece Premium Diamond Bit Set - Multi-Tool for Precision Drilling Porcelain, Ceramic, Glass, Marble (Blue, 9 Pcs) - Amazon.com

www.amazon.com

but there are as well for acrylic, that greatly reduces the chance of cracking...

Amazon.com

not sure the diameter of holes you are wanting to drill???

 

[GaryE]

I'm uncertain as well. Small, maybe 3/4 inch. I want to be able to turn a tap and drain, but a 45 gallon set up of 5s will only need to lose 15 gallons weekly. I'm happy with individual filtration - it's water changing I want to simplify. If do it as an overflow, I could run small changes by gravity almost daily. If I'm happy with it, I can do the same with my tens and reduce the active time by a lot.

 

[Magnum Man]

I'm sure you'll want to go with plastic bulk heads... but a quick search, this brass one, can do 3/8 inch ID, and 1/2 inch NPT outer... and still requires a 3/4 inch hole to insert it into... i would guess that's likely the smallest practical size, so you will likely be needing to do at least 3/4 inch holes

Amazon.com

 

[Magnum Man]

3/4 inch diamond glass drill bits...

hole sawing glass, with no pilot drill bit ( proper for glass ) is going to require a drill press, and a way of blocking your tank, to hold the hole saw steady, until you get a significant groove cut...

Amazon.com

 

[gimme30]

You could probably get away with a plain ol' glass cutter if you've got steady enough hands and something to trace around.
I should have tried it but, you know, I'm American. Why do it by hand if you can do it with POWER!!