Looks like a bit overpotted - pot and amount of media too large for size of plant. I prefer to use the smallest pot and amount of media that will just accomodate 1-2 yrs growth. My oncidiums similar in size to your's are in a 4" pot.
The roots look great!
I am inclind to think fungal also - but not too much experience with it. Are you able to get any any fungicides in your location
Ryan - what is the active ingredient in Clearys? Is it a systemic fungicide?
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DaveW
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