How do I get rid of this brown diatom

[newtomarine]

 

[JackDE]

You're going to have to post your parameters and all relevant info RE: your tank.

 

[Diesel]

No3?
Po4?
Temp?
PH?
What kind of flow in the tank?
Livestock?
What and how much you feed?
Skimmer?
Reactors, GFO, Bio-pellets?
Refugium with macro's?
FTS of the tank?

 

[twilliard]

And how old is the tank?

 

[newtomarine]

I turned the lights down and it's gone now