What in the world is growing w/ my chid!?

[SP2340]

Hi all. I went outside today and found something growing with my orchid.



I guess it's a type of mold. But I don't know how it grew. I recently installed a fan to give them air circulation:



They never had aircirculation and now that I give it to them they grow mold!? I water them every four days because it's so hot here in South Florida... I figure that gives them time to dry out enough.

Next watering I'll use fungicide but I'm a little baffled.

Do you guys think maybe I watered to often or maybe that mold likes air circulation?