Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
As the pictures above show:
Leaves and stem in the air, roots in the tank.
No need for soil.
Make sure there is reasonable light up there where the leaves are. Chinese Evergreen, and most of the plants we are talking about are low light plants, when grown as house plants. If you want high nitrogen removal, though, you will have to provide more light. I got the best growth out of Pothos when it was in a west facing window. I used a curtain to keep the direct sun off, but it was a pretty bright location.
If you want to do a plant in an HOB you could fill the HOB with lava rock. This is very good to hold the upright plants, and will grow lots of bacteria for the aquarium.