Blue-ish circular stuff on phal orchid roots ):

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22C / 72 F is acceptable for Phals. They will grow and dry out slower than they would if it were warmer. They may run into trouble when it gets much below 18C / 64 F for any length of time. They do best when it's routinely 25-35C and humid, but many people flower them just fine in typical home temperatures.

I wouldn't treat the roots with anything. That mold isn't harming the living plant. Regular drying between watering will limit mold growth. Hydrogen peroxide can also damage roots. A drop or two is sometimes used just in the crown if a Phal. gets crown rot, but that is not what your plant has.