I'm by no means an expert on frog care. I know that fungus treatments involve dipping in certain anti fungals. This really though, is by watching videos on chytrid.
What I can say from being a herp keeper is see if any of your local vets treat reptiles or amphibians or able to give advice.
These are little animals so diseases progress quickly.
A Common treatment is Itraconazole. Again I would only use under the direction of an expert.
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