I just have a 10 gallon on its side filled with about 4 inches of dirt and plants planted in the dirt. If you do this make sure it is 'natural' dirt with no fertalizer of vermiculite or thoes little white beads. I use a small piece of plexiglass I glued in place to keep the dirt from leaking out of the screen top (now the side).
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1.1.0 Emerald Swift
0.1.0 Mantella madagascarensis
0.1.0 D. auratus (Spotted)
0.1.0 D. auratus
0.1.0 D. auratus (Blue)
1.1.0 Crested Geckos
1.1.0 Phelsuma lauticada (Gold Dust Day Geckos)(plus many babies)

If I had only known, I would have been a locksmith - Einstein