Popular in Europe, underwater gardens let you create fantasy landscapes. Here's your opportunity to experiment with aquatic plants you might not be familiar with. If size and weight are considerations, remember that a 10-gallon aquarium, when full, will weigh approximately 100 pounds. Choose plants for form, color and texture.
Small gravel does a good job of anchoring plants and gives roots something to hold onto.
You can buy aquatic plants from pet stores or mail-order companies for anywhere from 50 cents to five or six dollars per plant. Accent your garden with driftwood, stones or volcanic rock. Create terraces by placing flat stones on their sides and pushing gravel against their backs. If you use driftwood, soak it in water for a while to ensure that it will sink and not float. If the garden is large, use a filtration system to help remove dead plant material and maintain clarity.