I don't have a digital camera but maybe I can borrow one from work. If I can I will take a few pics but I am not sure if I can post pics here. If I can't I will be happy to email to anybody that wants.

Those plenum systems seem to be a really good idea from what I have heard about them. When I was in Hawaii I had my aquarium unknowingly set up like that. I tried to mimic an undergravel filter (because I had used undergravel filters for years) and have sand on top of that, I used a tightly woven piece of cloth to seperate the sand and gravel. I never had any problems. I had a yellow tang, a goat fish (that died a few months later when the power went out in the barracks), cleaner shrimp, a mantis shrimp, a clownfish, and a blue damsel. They all did fine in my 20 gallon aquarium.

In one year I am going to move so if I can have a tank run fine for a year then I am not going to complain. Besides if you have those snails that burrow in the sand and keep it clean (like nature does) then there should be no problems.