I keep a pair of these and they are high humidity turtles, so jack that up. Heat & humid, maybe that'll help the shell. I would vet the turtle if ya ask me. And get him on fresh food with vitamin supplements and an earthworm or two could help. Give him a shallow tub to soak in too. Make it deep enough so he can submerge himself and touch the bottom. aaannnddd....they like to dig under substrate. make that deep too.