Phalanopsis leaves yellowing
 

What am I doing wrong. This is 3rd leaf that has yellowed and fallen off in a month. Any advice is appreciated!

Most of the time, it's a matter of the plant extracting chemical resources from older leaves and redistributing it to newer growth, because there is something amiss in the overall culture (too little water, or the inability to take it up due to "iffy" roots), but this looks 1) extreme and 2) from too high up in the structure.

The leaves are very wrinkled. It's not taking up enough water. That is either because it's not watered often enough, or it has poor roots. That can cause leaf drop.

Take a look at a sticky thread here. From the left yellow menu select Forums then Beginners. Near the top find The Phal. abuse stops here. Read the first few pages.

Thanks for for your thoughts! The leaves don't wrinkle until they are ready to fall off. I do think the roots are the problem. Once it's done blooming i will repot and take a look at the roots. When i buy them from stores they are just totally pack in moss so always a bad start for me. Thanks again

You can repot now. It doesn't affect Phals. in bloom. Don't cut off roots - you can't be sure they're dead.

I’ll try it. Thanks

second, and wanted to add that occasionally we even see a boost in growth with a repot, even when phals are in flower.
when was the last time you repotted it? or is this one of the new ones you mentioned? if it is, then certainly it will be happier when redone.

or it could be SODS (sudden orchid death syndrome). we have had this happen with about 4 or 5 phals (and one of our most expensive plants), where very suddenly the plant went from healthy to dead in like a month or 2. one after another all the leaves yellowed and fell until the stem was bare (and in most of those cases the roots looked fine). i have seen this mentioned occasionally around the webz and still there is no real sound reason that i have read or been able to hypothesize. we throw those cases away fearing some sort of disease or something. hopefully your plant isn't experiencing that!! best of luck

edit: on second look at the pic, is the spike coming out from that leaf node? do you see evidence of the leaf being split at the base from that spike? we have had some upper leaves die from spike interference, but if there were other leaves without spikes that also yellowed suddenly then you prolly got bigger problems under the hood and im grasping at straws

The leaves look very dark, could be genetic or it might need more light. Phals like bright, indirect light, and they also like to be kept pretty warm. Some phals give a burst of growth after blooming, so it might be getting ready to grow more roots it leaves if conditions are good.

I lost 3 Phals over the summer in a similar fashion. I'm fairly confident it was crown rot. I'm in east central FL so our summers are hot and super humid. I keep my orchids outdoors. I also wasn't militant about not getting the crown wet during waterings either.

I haven't had much luck with successfully saving a Phal once the crown rot sets in. Seems like a slow process that drops one leaf after another until they are all gone.

I've saved Phals with crown rot by putting a few drops of hydrogen peroxide just into the crown, leaving it for a few minutes, and blowing it out so the crown dries. I don't think the original poster has a problem with crown rot. It usually affects the center first.