A anhole would be ok for a 10gal but a day gecko or a leopard or a skink would need at least a 20 long cuz once you add a water bowl heat rock if that is what you are gonna use for a heat source. And something for decoration"like a fake tree or something else" it starts to take up alot of space... Think of it this way could you live with everything you need to in a 10 foot by 10 foot room??? try to give the critter as much room as you can afford..