Zygo issue

[Leafmite]

Someone in my orchid society swears by the original formula of Listerine to prevent the spots on Oncidiums/Zygos. He puts it in a spray bottle and sprays the leaves every week.

[estación seca]

You can read something about Zygopetalum growing and how to avoid leaf spots here:
Alan Koch, Gold Country Orchids, DVOS 2017 02 16

[Dollythehun]

I tried the Listerine route for years, with no visible results. I've also heard of a grower using Windex. Neem oil worked well for me. Some plants seem more susceptible than others.

[Shadeflower]

I read that listerine was too strong to put on leaves. At least that was for tomatoes. I'm sure I burnt some leaves when I used listerine without checking how to use it properly.
As a sidenote though one of my zygo's has developed a black patch on a leaf too now, that's karma right, me saying they shouldn't and then one decides to prove me wrong

[estación seca]

Listerine is alcohol with coloring and flavoring. The percentage is listed on the label.