I am so sorry, I have had a "new" animal take out a few of my long term "kids" in the past, its hard
the only thing I can think of is getting cultures sent out, I know its more $ but to many vets just throw baytril at reptiles, and maybe you can use/add something else to get to whats going on, and may save you $/investment potential in the future, or only for the lives of the animals.
is there any way to move any animals not showing signs anywhere else?
best of luck, keep us posted!
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hanging out under heat lights burns up my brain cells!!