I have an exo Terra 18x18x24 that now has a 6 month old water dragon. This summer I should be finished with his new enclosure which will be 5.5'x4'x7'. So what should I get that would be comfortable in the exo Terra? I would prefer a herp that will comfortable in it for its whole adult size. Any herp will be great, I would like it be able to use the hight this tank has but it's not a necessity. So what do you guys think should be my next addition? And I am asking now so I have time to do proper research before I acquire it. Thanks!