So for the past week or so my dragon whose only about 4 months old has stress marks on her belly about 80% of the time she is in her tank. I just moved her from a 10 gallon to a 40 gallon breeder, and in both tanks she had the marks. Her basking temp is about 100 degrees, cool end is about 75. She eats regularly , has normal daily bowel movements. She is about 8 inches in length. Holds her head up fine. As soon as she gets out of the tank to run around the house her stress marks go completely away. But when you put her back in the tank they come right back.