Root problem after repotting for the first time
 

I recently repotted one of my phals 10 days ago using Fertilome orchid potting mix. Everything seemed fine and I went on a brief trip 5 days later and when I checked the pot today after my return, I noticed the phal was leaning even more out of the pot as if it was pulled out a little. I checked the lower roots through the plastic pot and shocked to see a few dark gray roots with white fluffy fungal growth. I've attached some pictures that hopefully can help.

I'm new to orchid care and thought I was doing ok with repotting my phal. I really want to save it since it's one of my first orchids I brought home. What can I do to remedy this?

They're often somewhat unstable after repotting. Falling sideways would not be surprising.

What was the previous medium? Are these in your house, or outside? What is the relative humidity in your house?

Those roots might already have been dead. Normally white fluffy mold only grows on dead plant material, and does not kill living material. The leaves look OK, and the remaining roots I can see look OK, too.

The previous medium it came in when i bought it was mostly orchid bark and what looked like maybe little pieces of sphagnum moss mixed in? But mostly orchid bark.

The roots were actually very healthy when I first took them out of the first potting medium for rinsing. They were plump, stiff, no signs of rotting when I rinsed them off with water. I'm just shocked to suddenly see the ones through the pot showing signs of possible rot at the moment. My phals have always been kept indoors and have been doing fine up until 10 days after repotting this one in different media (made of Canadian sphagnum peat moss chunks, orchid bark, hardwood charcoal, and lava rock)

Could the roots be in shock which is causing them to die? What should be done now?

Phals normally transplant without shock, even while blooming. There can be root damage with repotting. I would not repot them now. I would continue to water again when the roots you can see become silver-dry, and wait to see how the plants do.

When would be a good time to repot then? I'd hate for it to sit in this mold and have the mold spread to other roots and other parts of the media. Is there a safe fungicide to use?

Edit: I also noticed there's condensation in the bottom portion of the pot, near the section where I see the mold. I haven't watered my phals since a week ago and the other phal pots are fine with no mold or condensation. I'm guessing this new media is holding in more moisture where there's extra peat moss.

It's still warm in LA so you can repot. In a super-high humidity climate I would either learn to use pure sphagnum moss, or use large bark.

I have the same thing happening but it seems to be with the medium i had from the orchid show orchids. If the mold only grows on dead material, does that mean its ok to have in your pot? its not going to kill the live roots right. I went ahead and changed the medium so it has fresh medium for my cattleyas

---------- Post added at 12:59 PM ---------- Previous post was at 12:58 PM ----------

also does it matter if the plastic pot is black? it does have drainage holes at the bottom but this has happened to two of my cattleyas already.

Based upon those photos, the biggest problem is the medium being way too dry. I would run tepid water through the pot for a few minutes, wait `15 minutes or so, and repeat the drench. After that, it'll hold moisture better.

To the OP's question and Tasha's, as ES stated, mold consumes dead tissue, not healthy. For that small amount of mold, I'd not be in the least concerned.

the media at the bottom of the pot is bone dry. The roots look silvery and shriveled. I look at the state of the roots to see when they need watering so while they are green they are fine and once they turn a bit silvey/whitish I water them but since the bottom is so dry I am suspecting you are watering from the top and not soaking the media enough.

The best way to water them is to stick them in a container of water. This way water seeps into the container from the bottom and forces old air out of the pot. After a 15-30 minute soak you put them back again. Then water again when you see the roots change colour

That works, and I have sometimes done that, but I believe that a top-down watering method is better.

If you place a pot into a container of water, one of the first things that can happen is the medium floating out of the pot. Even if that doesn't happen, as fertilizer residues and plant wastes dissolve in the water, they then have the opportunity to spread throughout the medium to be absorbed more broadly.

By watering heavily, top-down and letting it immediately drain, especially when using a water breaker to turn the stream into "rain", you get more aeration of the medium and flushing of the residues.