White fuz in my bark medium!

[Devogenes]

Hi friends! New orchid keeper here.

I've picked up two phals and an oncidiu over the past couple weeks after wanting to join the orchid world for a while. So far, things have been going okay.

One of my phals started dropping some of it's flowers a few days ago. The leaves and stems seem healthy to my eye so I haven't been worried. But yesterday I noticed some white fuzzies in the bark medium.

There's a picture attached. You can see it near the bottom of the container. There's a few patches like that.

Wuh oh! Does this call for emergency action? I assume this stuff is mold or some other fungus. Is it already too late? Should I repot into a new medium and was off the roots?

Thanks for your help, flower folk!