With Russian tortoises, humidity plays a part, but he also needs exercise (a big enclosure), a varied diet of tortoise-healthy foods and real sunshine.
This little guy has his own 5 feet by 4 feet indoor enclosure. But I live in Minnesota so no out side time yet I feed them kale romaine sometime. Spring mix mustard greens. Red Leaf green leaf. I mix it up every time. And in the summer it will get lots of different kinds of fresh weeds.
The top of his enclosure for now until I get a piece of fiber glass made and yes these a humid hide I just have troubles keeping the coco fiber damp all the time I usually have been getting in wet every couple days after researching a couple weeks ago