Thanks for the feedback re: blyxa Texas. I've never grown it before, so that's good to know.
I'm hoping this will end up being medium light, it's going to be high-tech with 20oz paintball CO2.
I really like this piece of wood (or pieces actually, there are a couple small branches mounted together). I agree with the comments about spookyness. The rock was called "Okho stone" when I bought it, no idea if that's a standard name or not. It was hard finding pieces of uniform colour since there seemed to be both brown and greenish types.