why are my leaves going yellow (moth orchid)

[fortis]

You might want to put this on a separate thread so it will get more attention. Based on the photos it looks like a fungal or bacterial infection. Fungal rot is common in Phals. Do you have access to fungicides/bacteriocides? It also looks like there are 2 plants in the pot. If this is the case I would separate them and put in individual pots. Then I would look at the roots of the infected plant, remove any rotted roots (dark, mushy) and leaves, and repot/treat the plant with fungicide/bacteriocide.

Susan

Thanks a lot, Susan,
What kind of fungicides/bacteriocides would you recommend?

Fortunatas