ok i am thinking about buying my whites treefrog a new cage and i was wonderinn what would be better for him a 20/29 gallon tall tank or a big version of this Petsmart.com - Reptile: Habitats & Accessories: Reptariums: Exo-Terra Glass Terrarium Reptile Habitat
The taller the better. Personally, I think the fancy glass front opening tanks are a waste of money, but that's just me. You can make a great habitat out of a 29 gallon for one frog. If you want to build something even bigger, you can do a 37 gallon, which is the same footprint as a 29, just taller. Then if you want to get another frog, you already have the room.
I agree with Liz. The 29 would give the frog more space to explore and it has a larger area for you to work with in order to be able to plant plants, and add a water dish, and have branches for the frog to climb on...