I found a hatchling outside my house in the street about 6 weeks ago or so, maybe more. I'm a teacher, so I decided to take him to school for the kids as a class pet. He did fine at school but when I brought him home for the summer, I began to notice some changes in his shell color - some whitish discoloration on his carapace. It started on the very top center of his shell (the top four scutes, I think they're called?), and has now spread in a straight line pattern traveling across the length of his back. The white sections are hard to the touch like his normal shell; his behavior has changed - not lethargic or anything. Still eating fine - his shell is about 2 1/2 inches long now. Never had a turtle before, so I'm not sure if this is normal or not.
I made some changes to his habitat when I noticed the discoloration getting worse. For instance, never had any trouble with water quality at school but it was very cloudy here at home, so I got a water filter that cleared that up over night. Also some drops to make tap water safer for turtles, and a cuttle bone for calcium in the water. I've got his tank right in a window that gets direct sunlight 7-8 hours per day, with a dry dock and lamp right above that he uses pretty often.
Is there something I'm not doing right? Please take a look at the picture and let me know if this is normal for a very young red-eared slider. Thanks!
