I would cover the glass bottom with special kitty all natural kitty litter, then I'd spread some Dolomite, and high yield muriate of potash on top of the kitty litter. Then I'd mix in 30% of a 20lb bag of the natural kitty litter with the mineralized topsoil, the natural kitty litter is used because it has a high CEC for gathering nutrients, and releasing them at a later time back into the water.What percentage of kitty litter do you use? That's a great idea. I use it to plant my lilies and lotus in my pond.
I've never heard of the Azomite but I'm going to try it in the tank and my veggie garden.