What a pleasant surprise to see an article on underwater gardens! I wish I had room for a giant tank, but here's my 4-gallon hex tank on my dresser. It's a fun hobby. I used gravel, but the sand looks nice in yours. I have so many that they take the place of a filter, and I do 25% water changes once a month (or so...). My fish are healthy and reproducing like mad, like guppies will do, lol.
LOL, it's only neat and tidy because I just removed two logs with more java fern on them, and changed the water--thanks to the article! I do have too many ramshorn snails. The guppies are just common "feeders". It's amazing how colorful they become when not in the crowded, dirty, unplanted tanks in the stores.