I use the compressed eco earth. One brick makes a ton so take it slow. I usually break the brick in half and then add more to the water as I go as its needed.
I just used one large bag of Forest Floor, 3/4 brick of Eco Earth, and one bag of ReptiBark. I was then able to add a thick layer of substrate to my 40 gallon ball tank, my 10 gallon Hoggy tank, and my 24"x20" GTP cage. With all that I still had some left over. I have about a 2" layer at the thickest part with only the hotspots being thin. I make it deep because I have live plants so they need it.
You could probably use a small portion of each bag and have a ton left over for the future.