I work in a nature center which has numerous reps and amphibs. Our eastern softshell's shell has recently begun to crinkle around the edges as if it was drying up, and looks pretty bad. There is a lump on the carapace where it attaches to the plastron. I also noticed today that it seems to be gasping/breathing with difficulty. Size: 3.5 inches. Tank: 20 gal. Can anybody help?