I have a pair of D. Azureus that have been breeding succesfully for over a year. I have had 3 tadpoles grow into froglets that have deformed back legs, they eat and get aroung fine but have back feet that are turned upward. Trying to fix this problem i reciently changed there diet from fish flakes to a comercial tadpole food, exposed the tads to UV light, and added methylene blue to the tadpole water. I have not had any born with bad back legs since these changes have been made but i recently encountered 2 cases of spindle leg both tads died before they finished developing. What could i be doing wrong?