[odin]

So i noticed these little guys (which really are tiny) bobbing up and down and seem to be attracted to the tank lights, they seem to of appeared at the same time as the hair algae which started growing.

Copepods via wikipedia

Heres a quick couple of videos of them, if they are copepods then i know the tank must be pretty healthy and wont be any issue towards my Opae'ula shrimp

[opae ula related]

I never knew the name and called it microorganisms. I have a closeup of it at the 30 second mark and I think they are the same thing?

[odin]

I never knew the name and called it microorganisms. I have a closeup of it at the 30 second mark and I think they are the same thing?

I think you are right! from what i have read they start off free floating alot then they like to perch on rocks and the likes when they get slightly older. Its a sign of a healthy tank apparently