From the look of it, let me guess. The tank is 1/2" thick, 96"x30"x24" (8 ft. x 2.5 ft. x 2 ft.). I'm not sure if just a single center 1/2" brace will make that tank withstand earthquake. If you have 3/4" glass, I guess it'll be ok. But then again, you're in AZ, I'm in CA. =)
For my 300G, 120" x 24" x 24", it's made of 1/2" thick glass, stronger than Starphire so don't need 3/4". It has triple 10 inch wide 1" thick bracing (to house 4 metal halides), with custom 3" wide 1/2" thick Euro-bracing all around 360 degree around the top side of the tank. The bottom are 1" thick (double 1/2"). It's going to be a heavy sucker.
How heavy is your tank?
I'm moving mine Saturday morning from the factory less than 36 hours away.