10mm glass, or 0.4", is the recommended thickness for tanks 18"-24" to prevent bowing. So providing the seals are good, 0.5" will be totally fine for your 23" high tank. Is it a new build?
That's gonna be pretty!
I'm impressed with the 45degee cut/end - you got this done or did yourself?
Same question as above: how do you access? Filters are above?