Mini Phalaenopsis Stem Rot?
 

Hi everyone, It's been about 2 weeks since I bought this mini Phal but I just repotted it because I saw a few roots rotting and saw that the lower stem is turning black. The crown and the leaves show no signs of yellowing or wrinkling so i'm not sure what to think. It's got one flower spike and the flowers on it are slowly drying up and falling off. It was planted in a compacted sphagnum moss (typical from the store) which is why I repotted it but i'm afraid it started to rot. I also sprayed the stem with alcohol since I just ran out of peroxide. What do you guys think?

Welcome to the Orchid Board!

The roots and stem I see look healthy. I would water when fully dry (unless you are using the semi-hydroponic growing method.) You can use a wooden cooking skewer to check moisture inside the medium:
Using skewers to determine when to water

The pot is larger than I would have used (unless you are using the semi-hydroponic growing method); with a smaller, more water-retentive medium such as this, I would pick a pot that just holds the roots. Still, the air spaces between medium particles should remain open and not clog up, so there should be air at the roots.

Thank you! I can assure you the pot is not as big as it looks. I just zoomed in on the stem to show the area of concern. I repotted it in Seramis, a porous, clay based medium and I water every 4-5 days because since the pot is small, it dries out faster. It also doesn't need to be repotted every 2 years unlike bark so when using media like this, you can choose a slightly larger pot to accommodate up to 5 years growth :)....Thanks for your help!!