Thank you hopefully!!!Hello Jack and welcome. The white marks might be growth lines, or possibly sediment from soaking him in hard water - I don't think they are anything serious, so don't worry, but someone more knowledgable than me will no doubt be replying later.
Angie (from Devon)
UVB lamp + Heat mat, it’s currently around 7inches to the top of cage, and the substrate we only settled for as there wasn’t any others, but noted.What kind of lighting are you using? How close is the basking light to the top of the tort?
Those white pellets/stones in the substrate and the substrate itself is the wrong stuff to use and can cause harm. Switch it out for fine grade orchid bark
Some of the markings looks like new growth. Some of it doesn't, unless it's just a reflection. The spotty ones, that are on the scute and not between don't look normal to me.
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