Here is a good read about them. http://www.amazon.com/More-Complete-...mplete+chondro

Ive never kept one in a tub setup. I house my adult in a 24 inch cube from http://pvccages.com/
The juvi I had was kept in a small exo terra glass cage like this http://www.amazon.com/Exo-Terra-Glas...arium+12x12x18

Regardless of what you keep it in a good humid substrate and misting will keep you humidity up. In my cage I use a mixture of Eco Earth, Repti Bark, and cypress mulch. I then mist when required and my sheds are perfect. I use that mixture because Im not a fan of each of those substrates alone but once mix they really make a great options that is no dusty, but not harsh and jagged either. It holds humidity well and it is visually appealing. Which is a big factor for me as my GTP is setup in a nice display style cage.