If you look at the copyright date on the first volume of Nature Aquarium World you will notice that it is fairly old. He wrote that book before he had most of the product he has today, like Aqua Soil. Almost all the picture you see today do not use the Oiso sand. As for substrates now, it's Power Sand (base fertilizer as you refereed to it) on the bottom with Aqua Soil on top. Works for me. Ryan