Black spot on zns. Roqueburne

[Pieceittogether]

Ok they started 6 month ago and now they are all over and all the leaves have similar patterns now. There no pests and root are in good condition. I looked for similar pattern; the answer was either fungus or normal on this type. I treated it with physan 20, but that was no point based on some of the literature of this needing something systematic vs outside. So my question I have no problem destroying it, however I see new growth and wonder if I should save it, but first I don’t know what is it a bacteria or a fungus or virus(harder to diagnose). Also how contagious this is I already I isolated it. What treatment route should i proceed with. This orchid get medium light, with RO water with Peter excel ca mg 15-5-15 1/4 tsp weekly. The medium is the original that came with from kalpantropicals. Thank u in advance for guidance

[estación seca]

Bump

Welcome to the Orchid Board!

I'm sorry nobody answered this before.

Zyginosia very frequently have a lot of spots that can't be diagnosed.

They are heavy water users. More pure water, like rain or reverse osmosis water, may prevent spots. Many people stand them in dishes with a quarter inch of water at all times.

They like higher humidity if possible.

I would try to correct your conditions if they aren't as above, and see whether this helps.

Edit: You can't tell whether it's a virus without testing. This doesn't look like typical virus infection to me, but virus infection can be asymptomatic.

I would try watering a lot more. Stand the pot in a dish of water.

I don't treat with chemicals unless I know what the problem is, and I know the chemical treats the problem successfully.

This could also be bacterial brown spot, since the spots are sunken. Have a look here; scroll down to "Bacterial Brown Spot on Zygopetalum." It suggests treating with a copper bactericide:
Orchid Questions Answers, St. Augustine Orchid Society, 2011

[Pieceittogether]

Thank you so much for responding. I greatly appreciate it. I do have it in a dish with pebbles for longest time, I took out once I started to see the spread. I did buy some copper as you suggested and I sprayed it this afternoon. I will give it a shot and see.