Is a good enough photo of the situation of the brooder and
a nice set up ...
Could you get some Probiotic from the feed store and add
it to the water ??
Oh one other thing if you could boil them up a couple
of egg's and feed one now and later another just remove
the shell and mash up...
Have you put any Probiotic in there water or used Save-A-Chick ??
Is there any kind of smoke around them including people smoking
in the area ...
Drafts of any kind ??
Do you have a photo of the brooder ??