Many sulcatas raised here in south florida have perfect shells. Some indian star breeders swear that a humid hide is just as important to proper shell development as diet and sunlight. I let mine burrow, because the temp/humidity gradient in a burrow cannot be duplicated. Add a steady diet of grass and weeds and natural sunlight and you'll get a nice smooth shell. Mine was adopted from up north, so he has some pyramiding, but I have already seen improvement in just a few months. I wish I had taken a height measurement when I got him. His shell looks more domed than it used to.
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-Jake

0.1 juvie L.t. annulata
1.1 adult/subadult L.g. californiae
0.2 adult Pseudemys nelsoni
1.0 sub adult Geochelone sulcata
0.1 mexican double yellowheaded amazon parrot