My vanda has been dropping a yellow leaf about every 4 days. I took a
look at the roots up close and there was blue rot balls all over.
Does anyone know what this might be or how I should go about treating
my vanda?

Don't know that I've ever seen anything like you describe, but if you think
it's rot, hit it right away with some peroxide. Could it be fungal?

For natural remedies and other information, try

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