Brown hair

[stanb]

I have a 29 gal bio cube with uv and protein skimmer. I also upgraded the lights to led and started about 7 months ago. I've been replacing about 5 gal of water every week but now have brownish hair starting to grow only my bird nest and now I noticed some on my live rock. What is this and how do i deal with it?

 

[twilliard]

Are you talking about the aiptasia ?
In the first picture that on the top of the rock is hard to tell cause of the light. But don't see it in the other pictures.
Maybe pictures with just the whites on

 

[stanb]

No, not the appraisal. Hopefully these two pics are better