I think one of my phals is getting really sick. I've had it indoors for a while, and one day decided to place it near the window so that it would get some sun. After that it started developing this big white spot, so I took it back in thinking it might be sunburn. But after further inspection I think it might be something more serious. Initially I thought only one leaf was having issues, but now I've noticed the other leaves have dark/mushy/mold like (and some with sap) spots, but only on the back of the leaves. I've attached pictures, from reading so far it looks like it might be some kind of bacteria?
Definately looks like some sunburn there on the last two pics. On the first three, have you tried cleaning off the leaf with a dampened papertowel or neem oil wipes? The white spots look just like water spots. Not really sure tho about the splitting on the leaves.
Maybe to be cautious, I would separate this orchid from any other orchids...quarentine time!
Maybe someone else will chime in!