That's good to hear!
Your setup looks very clean and nice.
One more thing I can think of... Do they have a warmer and a cooler area? So they can move according to their need for warmth?
I hope other members chime in and share their thoughts too...
Hi Jeane, How is your duckling behaving?
Is he/she walking normally?
Is he/she eating and drinking normally?
Is he/she in a warm clean environment?
Does he/she get picked on by the others?
How is he/she sitting/walking?
Can you post a picture of your duckling and your setup?
So many...