Finally pics of problem with phal

[greenpassion]

I had posted a few weeks ago about an issue with one of my phals, but couldn't get my camera to work. Well, today I was successful. To recap, this phal began to show something wrong with a lower leaf last fall. It continues to put out new roots and new leaves, but the 'disease? ' seems to be spreading. It's in a mix of orchidada, sponge rock, a bit of miss moss and charcoal. It is in an East window, watered with MSU fertilizer once a month. My water is well water. I've been spraying with physan 20 over the past 10 days. Any advice??