Your cages look great but i would change out the garbage twist ties with plastic tie wraps. Those can be sharp and can poke or scrape them or they could catch a tongue on it.
Personally i prefer playsand for their digging and i use one of those orange buckets from homedepot so they can dig down a good 12-14 inches <damp sand of course>
I wouldnt do pedilyte because of the sugar. Do straight water and there is a powder you can get from a pet store called reptiaide...buy the insectivore kind and you mix it with water.