Ok so I have an 8 yrs old brb living in a 12"Lx36"Wx18"H fishtank for the last 4 yrs. He's about 4.5' long n I just added a second level for more craw space. It's a little different but this is what I did. I came across an exo-terra small tall terrarium 18"Lx18"Dx24"H. If ur familiar with these it comes with a screened lock top. What I did was replaced that screen piece with a thick piece of plexiglass, cut out a 6" dia hole back right corner ish and flip the whole terrarium upside down. Now it sits on top farthest left side of fishtank. Setup as of right now is this: LOWER FISHTANK has heat pad on far right, middle has bathing container, next to that is ceramic tree sitting right under the hole to get up to second level, n last is waterfall on far left of tank. Bedding is that coconut husk stuff that expands in water. UPPER TERRARIUM: just aspen bark bedding n vase with bamboo growing out of it. It's pretty bare up top. Thinking about puttings up there. Can any suggestion on how to improve my setup or even rearrange everything. Any idea will be appreciated. Thanks advance. I'll post pics. later