I found a 40 gal breeder at a garage sale for a great price, so I bought it without hesitation. The dimensions are 36 inch length, 18 inch width, and 16 inch tall. I bought it on a whim so I had no prior ideas to what to put in it. I have a crestie and a leopard gecko and I want to broaden my horizons. What other type of lizards/geckos/fish could comfortably live in here through there whole lives? I also read some things about putting the cage up on its side, so its much taller for certain geckos; opinions? It has no lid so if I were to do that buying a screen lid that opens on hinges is a good possibility. Any help would be nice, thanks.