New glowing things?

[TikiBird]

Wondering if anyone might be able to tell me what these tiny tiny orange glowing bits are? They have just popped up in the last couple of days that I've seen. Are they good or bad? If it glows, does that mean it's good? [emoji848]

 

[Rybren]

Do they only glow when the blues/actinics are on? I've seen them every once in a while in my tanks and always thought that it was a type of coraline. It can be really noticeable on pumps after a vinegar bath.

 

[Tahoe61]

Red Valonia, a nuisance algae.