Thank you very much for your response. I thought the UVB might be the cause of it ~ it makes sense. Although softshells like to bask once in awhile they spend most of their time submerged and not exposed to high concentrations of UVB. I removed the UVB light to see if that helps the turtle’s carapace reform. I'll also confer with my vet to check on their diet.

Thanks again,

BK