Phewwww. And yes Coco Fiber Substrate I got from Repticon lol. Will it continue to stain?Yup! The skin was just stained by your substrate(coco coir I’m guessing), and the new skin coming in is the normal color. Nothing to be afraid of
Your baby is looking great!
Im not quite sure how old the darker ones are. That photo is from a guy who offered them to me for a ridiculous price. Like 300 a piece.Your tortoise does seem very small for his age.
But for one thing, those two tortoises are not being cared for properly. They are being housed together, and are pyramided. I would guess that they are a lot older than one.