I have not. I was waiting on my peacock moss to grow a little thicker on the pot on the right side, and I was going to cover it in the same manner. Its simply "artists canvas", which is 1mm hole mesh that can be bent. I sewed the moss on to it, then wrapped it around the pot very tightly. It makes it so I can remove the whole bunch of moss without disturbing the pot(in case of eggs inside) and rinse it during WC. However, I'll look into coating it in black sand. Sounds nice.
I really need to trim the wisteria, it has doubled in size in about a week. I'm just going to continue to replant it in the same area for a while. I'd like to get just two 15w or one 40w tube to go across the front of the tank, not so much to grow more plants, just to keep things evenly lit.
P.S. I forgot to mention that the substrate is actually 60 lbs of Eco Complete with 25 pounds of Estes Natural Deep River Gravel mixed in.