Fungus on Phalaenopsis? Leaf Disease on Dendrobium?
 

Hi

I'd like to ask for your help what's wrong with these orchids... first is what I think is a baby Dendrobium. While I was in the process of repotting Phalaenopsis and Dendrobium orchids, I found a baby orchid somewhere and decided to put it in its own pot. I assume it's a Dendrobium orchid because it looks like it has the structure of one. Recently, one of its leaf looks like it is rotting, but I don't recall leaving water on the leaf. Whenever my orchids' leaf is wet from my watering, I make sure to wipe it off. Is this a disease or is the leaf just rotting? The rotting seems to be spreading on the leaf... should I be concerned? Pic is below

Imgur: The magic of the Internet

On the second batch of pictures, you'll see white spots on the stem of a Phalaenopsis orchid. It just appared today. I don't know what they are, but I could scratch it off using my nails. Is this a type of fungus? If it is, could you suggest what natural remedies can I use?

Imgur: The magic of the Internet

When transplanting plants roots may get damaged. When that happens they may lose leaves because the damaged roots can't supply enough water to the leaves. That might be what happened to the small plant.

Phals often grow taller and leave old stem below them. This is usually dead some point below the growing crown. Many people remove these dead portions when repotting Phals. The living portion can usually be identified because it has healthy roots.

Mold may grow on dead plant tissue, but it usually won't damage living tissue. How long since you repotted this Phal?

Just 2 weeks ago... I don't know how old is the plant... I just got it from someone... The crown portion and/or the green portion that you see doesn't have any roots.. The existing roots are in the old stem

If the leaves look OK, I think the plant will probably be fine. I expect it will make more roots soon.

The leaves don't look fine actually... 2 big leaves that are damaged, and one fine looking small leaf. But I expect that it would grow roots too... just hope it can start showing signs of growth since I've adopted it two weeks ago. By now, I would have expected it to show signs of growth.

Orchids teach patience. You won't see a lot a change in a few weeks. They will respond to your care in a time frame of some months, so you will need to keep doing your best, and observe, make changes as necessary but gradually.

Ok, I guess it's normal to wait for wait for quite a bit of time before I could see changes... thank you very much.

Just an update, I sprayed the leaf with fungicide and it seemed to work... the rot-like appearance stopped spreading. I suspect the leaf may have fungus and was not rotting from watering.