hi, i have two peking ducklings that i bought from tractor supply co, ive has them for a little over a week, and they’ve been doing well, almost doubling in size. but today i noticed their skin is red? and little bits of fluff have been coming off in their pool when the swim. they eat mostly purina chick starter and some lettuce, peaches and peas cut up. they also have a mix of straw and pine bedding. any suggestions? thanks!