P.S. Here's a note from the future, from October 17, 2008, to be precise. The Rotala didn't hold up. I'm guessing that it needed more light than it was getting in my little tank, but maybe it was needing more nutrients, as well. There are a few small bits left, but most of it gradually turned to a dark brow mush.
July 20, 2008
Added a new plant to the aquarium
I found a couple of bunches of Rotala wallichii at The Fish Store, up in Sandy Springs, last Wednesday. I didn't know what it was, but it looked healthy, and had that reddish tinge that I've been thinking would add a bit of spice to the aquascape. I took one of the bunches home for a mere $4.59. We'll see how the red color holds up under my lighting.