Many times when ducks /ducklings drink water will come out of their nares. Is the fluid thick like mucus?
Can you explain your brooder set up and what you using for bedding? is it dry I mean it isn't soaking wet which can cause mold and bacteria to grow?
What are you feeding them and are you supplementing niacin since if your using food for poultry and not duck specific it most likely doesn't have enough niacin in it. I don't buy duck specific feed but poultry feed and i supplement with Nutritional yeast.
You could put some ACV with mother in their drinking water it's 1 Tab per gallon ACV can kill some bacteria. Other than a vet looking at them. And possibly you trying to get a video of your ducklings here so we can see what is going on. They may need an antibiotic but in Poland you may need a vet for that.

Can you explain your brooder set up and what you using for bedding? is it dry I mean it isn't soaking wet which can cause mold and bacteria to grow?
What are you feeding them and are you supplementing niacin since if your using food for poultry and not duck specific it most likely doesn't have enough niacin in it. I don't buy duck specific feed but poultry feed and i supplement with Nutritional yeast.
You could put some ACV with mother in their drinking water it's 1 Tab per gallon ACV can kill some bacteria. Other than a vet looking at them. And possibly you trying to get a video of your ducklings here so we can see what is going on. They may need an antibiotic but in Poland you may need a vet for that.
