Really well a 20 gallon could house 2 whites (their kinda big) a lot of people would say otherwise and say only one could fit, but I think 2 would do absolutely fine. Their easy to take care of and you can hold them, their pretty tame and will sit right on your finger untill you put them down. You can hand feed them too, but they do LOVE to climb at night, so the 27 gallon you have now wouldnt be to great as i dont think the plants suctioned on the glass would support them, but that wood vine thing in the middle, if you had a few of them going all different ways in a 20 gallon it would be perfect and very nice looking =) Although they wouldnt be able to climb to much on the suctioned plants like the anoles, im sure they would appreciate the cozyness/security of them!! =)