Steel Stand Build

[Fishgou01]

Hello, i'm completely new to building stands, and i don't know much.. I kinda need some help finding right steel size, and thickness.
My aquarium is about 40 gallon.(150L) size 32"x14"x20" (81x36x50Cm) Stand will be about same size BUT 40" (100Cm) high
Was thinking making stand from square steel tubing.. But i don't know much about steel structural strength.
Should i build from 2"x2" 1/8" thick? or Will 1.5"x1.5" do the job?
I want the stand to be very, very strong, and safe.. ( I will be adding thick wood on top of stand)
Design shown in images:

Thanks for any tips in advance.

 

[dattack]

That's a small tank. 1.5" will do . I have seen it done with 1" so long as there are some corner brackets.
You can post in the steel stand thread. I am sure there are others that might chime in.

http://reefcentral.com/forums/showthread.php?t=1330053&highlight=steel+stand

 

[windlasher]

Are you welding this? If not, how? 1.5 steel bar is hella strong. You could do 1" easily on a 40 gal. The challenge is making good strong welds and strategic use of corner/cross braces.

 

[Fishgou01]

Will be ordering from welding company. (As i don't have tools and such skill) Doesn't the "angled" beams in middle of 4 corners count as braces?
Outside welds will be smooth.. All inside and back of stand welds will be left as is for more strength.
(Top will have lager wood sheet and bottom also, will be adding 3 shelves on chains that will be connected to top inside of frame 4 corners)
1.5" and 1/8" thick then?
Weight wise it will still be lighter than me old wood stand/enforced cabinet.