Looks like I'd better just go ahead and build the full size tank. I was going for a mangrove thing, dragon fish, scats, monos, archers and mudskippers. I havn't really researched the fish yet, I just think that would be cool. I've got a piece of 3/8 acrylic, cut into a circle about 4' in diameter. I was gonna build a cube tank, about 4.5', fill it halfway with a 18' wide land area running across the back, mangrove trees and maybe some java fern. Should be pretty cool when done. I'll get it built, and then acquire the livestock. I don't think th dragons would be happy for long in the 20.