Hey,
I don't know the answer to that question. But I can recommend you this when you are going to use it for a big aquarium: take big, "ugly", cheap gravel like this on the bottom and put the expensive Amazonia powder on top. I did it with my 100cm aquarium and it's great how much money I saved for a nice layer of ground.
The plants with big roots (plants living emerged normally) love bigger gravel. Plants with small roots (like for a hc carpet) have a lot of roots in a small area, which is why they need fine gravel for their roots to go into the ground.