My 9 year old African Clawed Frog, Flipper has not been eating. He seems to be spending much of his time at the top of the tank. His water was changed, but he did not improve. His eyes look fine, his legs look fine (no red leg), but he is shedding more than usual. What is wrong with my frog?

other information: Flipper can ONLY eat floating turtle food. He has limb deformities and must be hand fed.