Can anyone please identify this?

[IslandLifeReef]

My rock seems to be covered in a thin layer of this stuff. I blow it off twice a week and get as much out of the water as I can, but I just can't seem to get rid of it. All of my corals, LPS and Acro are doing great as well as the fish. Parameters are:

SG 1.025
Nitrite and Ammonia 0
Nitrate <1ppm
Phosphate .03ppm
Alk 7.8
Cal 430
Mag 1330
Temp 76.8 - 78.8

I dose 0.5ml of NOPOX a day and skim on the wetter side. I clean the skimmer twice a week to keep it working at its best.

I have 4 fish that I feed half a mini cube of mysis each day and I dose 1 ml of reef energy each day for a 165 L tank.

Any idea of what this is and how to get rid of it? Thanks in advance for any help.

 

[Tahoe61]

An image in the tank would help. Based on that image a guess would be dictyota algae.

 

[IslandLifeReef]

An image in the tank would help. Based on that image a guess would be dictyota algae.

Thanks for the reply. Here is an image in the tank. I just blew off the rock, so this is the best I could do. The color looks blue in the picture, but it looks more white in the tank and brownish green when I get it out of the tank.