The Fox Farm is great soil. If you wanted, you can use a 50/50 mix of it with the sand. I would say to stick with a larger plastic bin for a lay bin rather than a plant pot. Rectangle gives more area for them vs round. However, if you are using a 50/50 mix, you can put a plant in the bin (add more soil at that area for the plant). They do like to lay their eggs up against root balls. The bin can easily be hidden behind plants. Since you’ve got a little bit of time before she becomes old enough for eggs and laying, you may want to think about going bioactive. It’s much easier than it initially looks and then the whole floor is her lay ‘bin’.
https://www.chameleonforums.com/blogs/intro-to-bio-activity.2429/ I started my girls off in regular no substrate enclosures and plastic lay bins. After much anxiety, I learned last year that at least the one doesn’t recognize her bioactive soil ‘floor’ as suitable for laying and will only lay in her plastic bin. So now I have a kind of stupid looking set up of a nice bioactive with a big pink plastic bin sitting in it.

For play sand, I’m very limited to whatever my local Lowes or Home Depot carries and I don’t recall brand...quikcrete maybe? One of our most experienced members suggests King brand, but I believe that’s only available in Canada. The most important thing is that it be the same type of sand that you would fill a child’s sand box with.
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