270 gallon plywood and glass tank

hi all in the near future i will be tackling the biggest tank i have ever done. this will be a 70 inch long by 30 inch wide by 30 inch tall tank. inhabitants will be SA/SC cichlids.

from my research i will need 1/2 inch glass for this build. this will be similar to a standard plywood build except i will be adding one more pane of glass to one side. also i am planning 2 center braces on the top of the tank along with a 3 inch wide cap that will go around the inside top of the tank

will standard exterior grade 3/4 inch plywood be sufficient for this build or will i need to do a 2x4 framework around it?

i will post up some pics of the idea later

here is a rendering of my tank. the stand will double as a dresser for my bedroom. after some thought i have decided to expand this tank to 36 inches wide this will bring the total volume to 330 gallons. more to come it will be several months before i begin this project though but it will get built.