Finally pics of problem with phal

[Sharon's Sheepdogs]

How long have you had this phal? I know of no diseases or fungus which cause reddening of orchid leaves, only too much light. Some reddening of the leaves is acceptable but continued exposure can cause dry black lesions. If the lesions are wet, you might have a bacterial disease.

I see you repotted the phal when you first received it. I always wait until I'm sure the orchid has acclimated to its new environment before I repot no matter how bad the media is. Even though none of your other orchids are showing symptoms of excessive lighting, the eBay seller may have been growing this phal in much lower lighting. Or this phal may have more sensitivity too light than other phal cultivars. Did you allow the phal to become gradually exposed to your lighting conditions?

If there are no other symptoms that would help to identify this as a disease, I suspect this phal had difficulty transitioning from the environment it had been growing in to yours which is why the lower leaf showed the syptoms first.

I assume you have isolated the plant. I would suggest you also reduce the lighting it was receiving & check the current condition of the roots. Let us know the condition of the roots along with any other symptoms which have developed & whether the phal has continued to decline or has stabilized. With that information we may be able to offer more help.

[greenpassion]

I think there's some confusion about which phal I was posting about. The one in the thread "Finally pics of problem phal" is about a phal I've had for several years. Around 4. It has been with 12 other phals on my counter under LED track lighting from Orchid Web. Up until recently, it, as all the others, have been doing very well. I have 7 all spiked and blooming. I have never had a better year than this. This particular phal started to exhibit that off color last year, and I just didn't really think it was a problem. It continues to put out new leaves and new roots. The one I think your referring to that I just repotted was a Sogo Yukidian that I'd just purchased from Ebay. Any time I receive an orchid that it tightly packed in moss, I repot in a mix of Orchidata, spag moss, charcoal, and fir bark. I have yet to have a problem with them acclimating. Anyway, this Sogo had few viable roots, probably due to it's being so tightly packed in moss, and likely overwatered, but it was only after I repotted it, like 10 minutes, that I took notice of the condition of the leaves. This phal I am 99.9% sure had either a virus or something comparable. I couldn't risk the health of my other orchids, so I destroyed it. The seller has refunded my money. I am going to cut off this leaf, continue to treat it with physan 20, and if the other leaves continue to show signs of what ever this is, well, it may be time to let it go. I do have it isolated in another room.