Who says an aquarium has to be all about fish? All over the world, planted aquarium enthusiasts practice the art of underwater gardening -- creating lush, natural-looking landscapes that live in the confines of a tank. These hobbyists communicate via the Internet, trading plants and information. They also trade pictures of their tanks. Each year the Aquatic Gardeners Assn., a group of enthusiasts 1,300 strong, holds a contest to name the best tanks in the world. Here you'll find the winning aquascapes of the past five years and get a taste of a whole new way to look at an aquarium. To read more about the art of aquascaping from California to Japan, read our story here.

-- Deborah Netburn

2nd place aquatic garden medium: 172 liters (46 gallons)

"Rhythm of Nature" by Harry Kwong, Ma Tau Wai Estate, Hong Kong