Help - Indentify White/ black powdery lesions- Fusarium?

[jesstnt3]

I am a relatively new orchid hobbyist. I have been successfully keeping Phaelenopsis and dendrobium for several years. This year I added a Vanda. (Blue Pacha)
It is growing well making new leaves and now a new flower spike- there is phenomenal root growth since I got it in March.
The lower leaves are wilting- no really discolored and not wrinkling, but are sagging down.
I soak it once a day for 10 -15 minutes and hang it back up to dry. Alternate one week with fertilizer and the next week water only. I have forgotten it in the soak bucket a couple of times so it has had 12+ hours in there at least 3 times in the past 5 months.
I can't tell if this is Fusarium and I am too inexperienced to brave whacking off the ends right now...
Please help a newbie!

[Roberta]

First, welcome!

I think I can guarantee that it isn't fusarium (which is really rare outside of the tropics)... that was a "diagnosis" popularized by a series of YouTube videos, causing people to do irreparable damage to a lot of previously good orchids. Don't cut anything!

Losing the oldest (bottom) leaves is quite natural. The plant is doing great. Perhaps give the suspect areas a bath with soapy water. (This will wash away a lot of stuff, and also kill bugs by drowning them.) If the problem comes back, then further investigation would be in order. It's really important to know what you are treating before deciding on a treatment. But looking at that vigorous plant, keep on doing whatever you're doing (except forgetting it in its soak... it does want to dry between waterings)

[estación seca]

Welcome to the Orchid Board!

Your plant looks better than 90% of Vandas people post here. With Vandas, pay attention to the roots. Yours look great. Photos you see online are of perfect plants selected from many others.

By way of example, I am extremely strong and healthy. I don't look anything like Brad Pitt.

[jesstnt3]

Thank you for the rapid replies! I will continue to keep her happy in the window and use some soapy water to remove the dusty accumulations.
Grateful you all think it does not require amputation of its amazing root structure.

[SouthPark]

Excellent recommendations made above already. Jess ------ you mentioned black powder - so could also look into mildew. If it is related to that, then maybe some suitable orchid-safe fungicide could be used as a preventative. I have seen/heard before that some mildew can grow on media (eg. rocks etc) very quickly ...... and can make growing media and roots a black colour.

It might not be mildew for your case, but could take a look into it.