Join Date: Oct 2008
Location: Salt Lake City, UT
Those look like shou stones to me. My advice is use long narrow plants, like Hair grass, these accentuate the effect of the stone, for an example you can look at the first scape of the tank in my signature to see how this looks.
That being said, UG isn't a bad choice to use with it either, since it has that grass look when it's grown in, just in a different way. I'd stay away from using HC or glosso though since they aren't -as- suited for this rock type (which is very slate-like and vertical) as UG or hairgrass. In fact a hairgrass background and UG foreground isn't a bad route to go. The good thing about these stones is that because of their coloration the need for a red plant or the like is unnecessary.
I see where you are trying to go with the hardscape, and could give you pointers on improving it if you wish, but it's a little difficult to do once it's filled with water! It depends on your current focus, plant growing skills or hardscape skills.
Aquascaper for life.