Mold or mealybugs on phal? Sequence of problems with new orchid

[thegirlwiththemouseyhair]

I've been struggling with a new-ish orchid that I bought in June. I inspected it carefully in the store and didn't think there were any major issues like pests, although it looked a bit dry. I repotted it when I bought it, put it in Fafard medium (medium-size fir bark and coconut husks; excellent for my other orchid which I've had for two years), and then saw some white stuff that looked like mold growing on the bark a few days later. I tried putting the orchid in a new medium. Since I couldn't find more Fafard medium at that time, I tried the orchid in Miracle-Gro (large chunks of bark, charcoal, and perlite). After several weeks in the Miracle-Gro, I was struggling with the watering schedule and found the orchid looked really dry and was losing bottom leaves. I found some of my preferred Fafard medium and repotted the orchid this past Saturday. Some of the roots had a bit of root rot, but the plant has still got lots of roots left, so I figured I could save it in a medium that I know has worked with once a week watering.

Unfortunately, this morning (Monday) I noticed white stuff growing on the bark and some of the roots and stem. I'm not sure if it's pests like mealybugs, or snow mold, or something, and I don't know what to do. Should I give up on this orchid and look for another one? It's really frustrating that I've kept one phal going for two years, but can't seem to repeat that with any new additions. Sorry the pictures are not the best; any advice is much appreciated.