what substrate for live plants and gymnos?

I am going to have a planted tank for my gymnos and oblongums, i am wonder what is the cheapest and best suited for gymnos and plants? I don't want spend a lot, its for a 46 bow. I was thinking 40lbs of flourite on bottom and quartz sand on top. this is my first real planted tank. Also what plants would best suite this type of set up? Any help would be great.