Does this look like shell rot? Hermann’s tortoise

[Appliedcello]

After Koopa’s soak for today I noticed some bubble like formations in the black parts of the plasteron. I’m very worried that it is the beginning of shell rot. Should I be worried?

 

[ZEROPILOT]

No.
It looks like rub marks.
Does your tortoise walk across anything hard?
At any rate you can rest assured that there is no fungus

 

[Appliedcello]

No.
It looks like rub marks.
Does your tortoise walk across anything hard?
At any rate you can rest assured that there is no fungus

I use top soil as substrate. She might be rubbing up against the food plate (I use a floor tile)? Or some rocks i scatter through the enclosure? Or her hide? Could be anything. But I’m so glad there is no fungus!