Glas thickness on deep tanks

[_erik_]

Hey! Sorry for another one of these annoying glas thickness threads..

Im planing on building a wide and low glas tank measuring 72x40x20 inches/180x100x50cm (lxwxh). Im planing on bracing it all around the sides (2" braces) of the tank with 2 additional braces going over the tank (4 or 6" braces).

Will 1/2"/12mm glas be enough for the tank?

 

[_erik_]

To clarify, I intend to "Eurobrace" the top aswell as the bottom of the tank.

Another question, do the braces need to be the same thickness as the tank itself or can I get away with thinner glass for the braces?

 

[Backfromthedead]

1/2" will work for that tank as long as its properly supported by the stand. If it was me, i would like to use 3/4" for the bottom panel. Im not a fan of the inset bottom bracing, and i don't think 2" strips would do much to reinforce it.

Make the top braces at least 6" wide and at least 1/2" glass as well.

Some of the more experienced builders here may have more insight for you. Good luck with your build.

 

[_erik_]

1/2" will work for that tank as long as its properly supported by the stand. If it was me, i would like to use 3/4" for the bottom panel. Im not a fan of the inset bottom bracing, and i don't think 2" strips would do much to reinforce it.

Make the top braces at least 6" wide and at least 1/2" glass as well.

Some of the more experienced builders here may have more insight for you. Good luck with your build.

Alright, thank you for your reply! 3/4" are insanely expensive here, 5/8" is doable... if I make the tank a bit lower, say 16" or 18" instead of 20" would 5/8" be enough for the bottom panel in your opinion?

 

[Backfromthedead]

Alright, thank you for your reply! 3/4" are insanely expensive here, 5/8" is doable... if I make the tank a bit lower, say 16" or 18" instead of 20" would 5/8" be enough for the bottom panel in your opinion?

5/8" would work great and you wouldn't have to reduce the height. You wouldnt need the bottom bracing with that thickness either. For the bottom panel, i think its pretty important that you go with standard float (annealed) glass and not tempered.

To be clear i think 1/2" would work fine for the sides no need to go any thicker until you get over 24" height. At 16-18" height with 1/2" glass sides, you wouldnt even need top bracing imo unless you wanted it there for whatever reason.

 

[_erik_]

5/8" would work great and you wouldn't have to reduce the height. You wouldnt need the bottom bracing with that thickness either. For the bottom panel, i think its pretty important that you go with standard float (annealed) glass and not tempered.

To be clear i think 1/2" would work fine for the sides no need to go any thicker until you get over 24" height. At 16-18" height with 1/2" glass sides, you wouldnt even need top bracing imo unless you wanted it there for whatever reason.

Okay, great! A somewhat related question; The side panels are siliconed to the sides of the bottom panel right? Ive made small tanks both with side panels on the side of the bottom panel aswell as standing on the bottom panel and both have worked for me. But with this big tank I really wanna dont wanna make any misstakes and Im trying to make it as durable as possible.

 

[Backfromthedead]

Okay, great! A somewhat related question; The side panels are siliconed to the sides of the bottom panel right? Ive made small tanks both with side panels on the side of the bottom panel aswell as standing on the bottom panel and both have worked for me. But with this big tank I really wanna dont wanna make any misstakes and Im trying to make it as durable as possible.

Ah yes, floating bottom vs stacked sides. This is a question ive been asking experienced builders for a couple years now and theres no clear consensus as to which is better. Most manufacturers seem to make their tanks with sides stacked on top of the bottom glass, whereas a lot of custom glass tank builders seem to use the "floating bottom" design.

What seems to be agreed upon is that with very tall tanks with very thick sides (3/4"+), floating bottom is the way to go.

Ive built tanks 55-75 gallons using both methods successfully. I have 3 upcoming builds: a 60x36x18 and a 36x30x27 which will be with stacked sides, and a 72x30x24 which will be floating bottom.

In the end i think it mostly comes down to personal preference. For your tank, if you're using the stacked sides, i would definitely use the 5/8" bottom. I would consider the floating bottom if using the 1/2" bottom.

Ive exhausted the limits of my expertise here, maybe BIG-G can give some advice as he is one of the more experienced builders that post here.

 

[_erik_]

Ah yes, floating bottom vs stacked sides. This is a question ive been asking experienced builders for a couple years now and theres no clear consensus as to which is better. Most manufacturers seem to make their tanks with sides stacked on top of the bottom glass, whereas a lot of custom glass tank builders seem to use the "floating bottom" design.

What seems to be agreed upon is that with very tall tanks with very thick sides (3/4"+), floating bottom is the way to go.

Ive built tanks 55-75 gallons using both methods successfully. I have 3 upcoming builds: a 60x36x18 and a 36x30x27 which will be with stacked sides, and a 72x30x24 which will be floating bottom.

In the end i think it mostly comes down to personal preference. For your tank, if you're using the stacked sides, i would definitely use the 5/8" bottom. I would consider the floating bottom if using the 1/2" bottom.

Ive exhausted the limits of my expertise here, maybe BIG-G can give some advice as he is one of the more experienced builders that post here.

Yeah, Ive searched quite a bit and its hard finding a clear answer. I think im going with the semi-floated bottom (side panels on the side of the bottom panel without lifting the bottom). Unless the fine people on this forum tells me its a bad idea...?

Im definitely going with the 5/8" bottom (with 1/2" sides). Im gonna eurobrace the tank just to be extra safe. My wife would kill me if a tank 230+ gallon tank breaks in our house!

 

[BIG-G]

I’ve seen several builders build with Inset bottoms.
I prefer to build on top of bottom pane.
It’s just what I’m used to doing.
Either way without a frame on the bottom you will need to have a solid stand that is truly level in both directions.
The last thing you want is any twisting once the tank is filled.
I would also recommend you place a sheet of foam underneath to eliminate pressure points.
For the glass thickness thicker glass will always add additional safety factor.
In my opinion 1/2” should be fine for this tank being only 20 “ tall, once the tank is setup properly as mentioned 1/2“should be okay for the bottom as well. because, it will be fully supported the only problem would be an internal pressure point caused by a rock or other scape/decorations inside.
I would try to euro and center brace with 1/2 inch as well.
If cost or availability is an issue I may consider dropping down to 3/8 For my euro but I wouldn’t go any less.

 

[_erik_]

I suppose since im planing on using extensive bracing I might aswell build on the bottom and avoid issues that might arise from doing the build semi-floating!

And a final question: Is 1,5mm appropriate spacing between the bottom and sides of the tank when you silicone it together?