My son bought a leopard tortoise a few months ago. The middle section of his plastron is soft. We have a lot of box turtles, a Russian, a sulcata, and a red foot that are all doing very well. We are stumped on this little guy we can't get a clear answer in substrate and humidity. He eats greens dusted with calcium. But he doesn't eat a lot. He has UVB and heat. He is currently on paper towels as we have no idea what's best for him. Any help would be great.