Just for fun, really. I think it looks more natural than a "clean bottom" tank with only the plants and such. Real river beds and lake beds don't look tidy and clean. It would be a plus if they lowered the pH, but I'm unsure if they do that. The fish seem to be loving them. They go under them, get inside the curls, and it looks like they're having a good time. I added more this evening, and my GBRs color has improved quite a lot since then. I threw in 2 tiny tiny convict fry, and they find little hiding places so the GBR doesn't eat them. It's pretty interesting to watch.
dread,when you get the bogwood get some Java fern, tie it to the wood and let it spread....very low maintenance plant, in my mind this plant will grow under almost any conditions...very hardy and looks wicked in a tank....