Hah! The only way my HC is 2" off the substrate is if it gets uprooted and starts to float! :lol:
Mine form a 1" high mound that increase in diameter. My Riccia is taking up so much ground space that I've pretty much given up on having the HC spread as a ground cover. What I have been doing is let bits of it grow in a floating mat of Riccia...sorta an in-tank emersed environment.
Don't mind the bubbles, I have a Red Flame Gourami that's trying to impress an imaginary mate.