Hi,
I think that the temperatures are fine, although, I think that the critter holders, are not adequate enough for your charges. I would try and get them into something like a rubbermaid, set up if possible. What are the temperatures in the house or area of the room they are being maintained in?
I would suggest to you to build a rack system for your bloods if you are handy with tools, as the rack system is the best way to control and regulate temperatures and humidity, while at the same time, giving them a more stable environment to grow in. The plastic critter cages, don't really afford them the security and or insulation they need as babies. If you don't know what a rack system is I can supply you with a plan for building one. They are not hard to build and require some basic tools. I think that the cage that you are going to be putting the animals into is way to large for babies of several months old.
A smaller cage like a plastic shoe box, is actually a better enclosure for a baby or juvie. A sweater box like the Rubbermaid, I believe 2221, might be off on the number, can make a better cage, as you can them provide them with a gradient and several areas within the box, to hide in (humid hide, and a dry hide spot).
As for the dry looking area that you suspect might be fungus, I would wait and see if it sheds out with the next shed. If it doesn't then I would take it into a vet and see what the diagnosis for that is, as it is not easy to diagnose unless done by a vet with the right experience. Good luck!
- Angel
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Sometimes on your way to your dream, you get lost and find a better way!