tortoise question

First time posting on here, I hope I uploaded the pictures properly. A light green spot appeared on my tortoises shell near his head. I tried scrubbing it away with water and a toothbrush. Nothing worked. Then I noticed the other mark closer to his tail. Is this the beginning of shell rot...

Hello all, I have a bit of a problem and wanted to get your advice. My 6 year old tortoise, Pippi, spends most of her time outdoors, only coming inside at night. She has a run that she is put in when she cannot be supervised that is half indoors (filled with hay), and half on the lawn so she...