What is this junk?

[Jake_the_reefer]

So I had an unknown algae outbreak. After a few water changes and blackout it was beaten. Today I added egg crate frag racks to the tank and within hours its covered in this dark brown stringy algae. Tank is barebottom and relatively high flow.

 

[SandJ]

I don’t know what the algae is, but anytime I add anything new to the tank, like a new frag plug or frag rack, it gets costed in this algae. Then it just goes away.
My unprofessional opinion is that the brand new material contains something that feeds the algae and it stays there until it is used up.

 

[Jake_the_reefer]

I don’t know what the algae is, but anytime I add anything new to the tank, like a new frag plug or frag rack, it gets costed in this algae. Then it just goes away.
My unprofessional opinion is that the brand new material contains something that feeds the algae and it stays there until it is used up.

It's just odd it was only like 2 hours before the algae showed

 

[SandJ]

I usually notice it the next day.
Also, if I wash my frag rack off in tap water I get algae growth on it.