Beardie Dragon, I have one and it is my favorite pet in my life. They are so cute as babies, get a female, as they get 18 inches or 20. Mine is currently like 1 year and 7 months or so. It is in a 45 or 50 gallon, but I think you should get one dragon in a 40, that is small but enough. If you want to get 2 Dragons, you can do 40, but make sure you have extra basking spots and lights, if you get a male/female, don't as males sexually mature in 6 months, while a female takes 3 years. So if the male gets horny, it wont be good for the female.
Get a beardie, there are cool morphs, and love to be held and have baths.
1 Bearded Dragon
3 Red Eared Sliders
4 Hermit Crabs