5 ft 125 gallons reef tank glass thickness

[patmos]

I plan to build a 5' X 2'X 20" reef tank. A friend with some experience will help me. the project is inspired by this thread :
http://www.reefcentral.com/forums/showthread.php?t=2572260
I have some questions before embarking on such a project as I live on a remote island.
I am in doubt whether using 10mm glass is a safe option.
From this link it is said to be safe
http://www.theaquatools.com/building-your-aquarium
I need advice. I hesitate between 10 and 12mm ( 1/2")
I was also reluctant to brace the tank mainly for aesthetics purpose
After reading so many articles...I hesitate: to brace or not to brace ( euro-brace)
If braced, should I do both bottom and top bracing?
Is it necessary to center brace?
Any advice is welcome

 

[fishgate]

Never heard of them. But 72" (6 foot) are 1/2".

 

[patmos]

Thank you. Better going 12 mm. I need advice on the bracing.

 

[darrelljm]

I have a 5ft. 125 gallon and the glass is 3/8"