Shell rot ??

[Réformons]

Hi sorry if i dont post this at the good place im new to the forum. I would like to know what you think about this, is it shell rot because i have 12 baby yellow foot and 9 of them got this. they use to be in the terrarium with moss and a changed them to black earth when i saw this 2-3 week ago. 2-3 have a lot like this the other have almost nothing. i keep my terrarium between 80-90% humidity but the substrat is dry. Ill post picturre with my phone

 

[Réformons]

This is one of my baby

 

[Réformons]

This is the enclosure

 

[TestudinesSG]

Cute little fella! I’m not an expert, but your little one looks fine to me. Mine usually get markings on their scutes like that, but they go away as they grow. Just keep an eye on them and also watch their behavior.

Humidity for hatchlings usually needs to be higher (around 80%) and make sure that they are getting full spectrum UVB for about 10-12 hours a day. Other than that, as long as they can bask and dry out, you should be good to go. Looks like you’re already doing everything correctly.