BLUE TONGUE SKINKS

1.) how far off the ground do they need to be to feel comfortable. What I mean is, if I had an enclosure two feet off the ground would the lizards feel less secure and be more skittish? I have a 3 level rack, and I want to put them on the bottom level - but I don't want them being stressed

2.) how many Emerald Tree Skinks can live comfortably in a 4x2x2?

I don't know anything about emerald tree skinks but after a quick Google search through the images of "emerald tree skink enclosures" it looks like the general consensus on the enclosures are at least 3-4 feet high - so aboreal enclosures that are about 36x18x36 (3 feet high). I haven't seen any that look lower than 3 feet. There's also this girl that I found on YouTube, RedsFaunaverse, giving a basic EMERALD TREE SKINK Care & Information rundown. She seems pretty cool and informative and looks like she cares about her animals' care and health. The video is 19:38 minutes long but about 5:20 of it is spent on an intro. I went ahead and copied the url at the time she starts getting into the care info in case you're interested in not watching the intro.

I only did maybe 5 minutes of search on this, but like mentioned, I'm pretty sure they'll be comfortable with an arboreal enclosure with some substrate thickness at the bottom for burrowing. In the video she mentioned they do this sometimes when they're scared or nervous. In the video, she's using a 36x18x36 enclosure and she has about 4-5 of them in the same enclosure while looking like they're comfy.

They look like really cool lizards though and I'm excited they look cohabitable! I might get myself a few in the future. :D

There's also this video, Emerald (Green) Tree Skink, The Best Pet Lizard? by Clint's Reptiles (cool dude) on some more info on the little guys. I didn't watch the video so I'm not sure which information is shared between the two YouTubers, but a lot of the information should be the same anyway.

Good luck raising the little guys!

Edit: just realized you mentioned you were putting them in a rack system, but I think as long as they're in an enclosure that's 3 feet high they'll be comfortable...but I might want to put them a little higher in the rack system then the floor/bottom.

From the research I have done while waiting on my captive bred emerald its really dependant 9n their space and height. And if they are eild caught or captive bred. And their peronalities. Thry can be personable and interractive when they feel safe and settled. As for being on the floor I really dont see an issue. Thry are kind of odd for small lozards in that they dont tend to flee humans when they have trust. One of Clint's videos (i think its the one with another youtuber inn it i forget which one) he even puts an emerald on the ground and it just crawls back up onto him. So I dont see a geound level being a problem as long as trhy can climb alot inside.

As for how many? Thats relative to how you want to work with them. They are more of harem cobers so 1 male to multiple femalles. Males are known to fight no matter how much space you give them so be leerry of housing more than one and be prepared to seperate them. I think redsfaunaverse on youtube has a sizable space and has 5 or 6 vomfortably. Just remember they need Verticle more than Horizontal but they will use all the space

Edit: I just realized those videos were linked above I apologize lol