My little brothers' red eared slider's shell is turning white but it isn't soft. It has got a UV light (its fluorescent tube light used in fish tanks, we couldn't find any other kind) and its food has D3 in it. It has also been slow recently and today is not eating, please help. I would take it to the vet but there is no vet here that looks after turtles. I have added a link to a picture of its shell below. Thank you in advance for your help
https://www.flickr.com/photos/143542980 ... ed-public/