Algae growing in terrarium, on orchids...okay or bad?

[ColoradoBirddog]

I noticed algae growing in the bottom of the terrarium, among the hydroton media. Ive used bleach water before to kill it. However, its growing on the orchid mounts, and pots.

Terrarium is mostly enclosed at top, with 2 fans inside running 24/7. Humidity is provided via a fogger. Bright LED light, as well as direct western sunlight in the afternoon. Daytime temp around 80f.

I have noticed that there is a...musty (?) smell when I open it. I thought this might be due to the algae. So, is this stuff worthy of concern, eradication, or is it harmless? If I need to get rid of it, what would be the best course of action?

Picture included is one of the mounts, as an example.