12'x3'x3' Tank planning

[Freemananana]

I've been doing some 3D modeling, planning, budgeting, etc for a 12'x3'x3' (~800g) plywood build. I am limited by the availability and cost of semi-local glass. With only 3/4" low iron glass available (no 1"), it limits my options.

1) 72"x36"x3/4"
2.8 safety factor
Two Windows

2) 48"x36"x3/4"
3.8 safety factor
Three Windows

I've read that most modern tanks are being built with a 2.8 safety factor, referencing 40B and such that are popular at fish stores. I have also read that 3.8 is the general suggestion. I'd like opinions on the options I have available. Obviously going with 144"x36"x1.5" acrylic online or something like that is just going to add a ton of cost that I don't have budgeting at the moment.

I do plan on bracing the tank every couple feet across the top and have 2"+ of overlap between the glass and wood for a good seal and such. A lot of suggestions are based around 'appropriate' bracing, which is vague.

So what size panels would you go with? Also, what kind of bracing do you suggest (how far apart, boards or rods, etc)?

 

[boldtogether]

I've been doing some 3D modeling, planning, budgeting, etc for a 12'x3'x3' (~800g) plywood build. I am limited by the availability and cost of semi-local glass. With only 3/4" low iron glass available (no 1"), it limits my options.

1) 72"x36"x3/4"
2.8 safety factor
Two Windows

2) 48"x36"x3/4"
3.8 safety factor
Three Windows

I've read that most modern tanks are being built with a 2.8 safety factor, referencing 40B and such that are popular at fish stores. I have also read that 3.8 is the general suggestion. I'd like opinions on the options I have available. Obviously going with 144"x36"x1.5" acrylic online or something like that is just going to add a ton of cost that I don't have budgeting at the moment.

I do plan on bracing the tank every couple feet across the top and have 2"+ of overlap between the glass and wood for a good seal and such. A lot of suggestions are based around 'appropriate' bracing, which is vague.

So what size panels would you go with? Also, what kind of bracing do you suggest (how far apart, boards or rods, etc)?

Obviously the larger glass would offer better viewing but you can't argue the safety factor difference. 3/4" is plenty thick for that size tank especially with a 2" border....and vertical bracing won't be difficult but the real fly in the ointment is horizontal bracing.
Horizontal bracing is by far the most important bracing followed by corner and top bracing tied for a very close second. I would recommend framing the glass with the 2" side of a 2x4...if that makes sense. And the top of the framing for the walls be the 2" side of thhe 2x4 as well. Of course you may decide to use heavier wood like 2x6 etc..but the idea is still to use the side rather than the flat of the boards when framing.
For the vertical bracing, many builds have gone with 16" on center, but I like 12" on center and doubled corners...
Follow the framing with the plywood inside, obviously, but don't scrimp on the outside sheeting. 1/2" is bare bones minimum and don't scrimp on the screwa either. 3-4" apart on every stud may sound like overkill and it probably is....but it is cheap insurance.

 

[DIFish]

Go with the bigger panel, it will be plenty strong as long as you brace the top.