I hear about heat living in Phoenix. I'd never build a large reef tank
without a chiller, they do much better in the low 70's. I've gone with
heat tollerant plants and fish which can handle the mid-80's the tank
runs in the Summer. Fortunatly this is easy in freshwater.

I've not used flourite, I've always been partial to laterite (cheap
from ceramic supply stores) and 2mm sand.