Algae help

[STLJam]

Having a small issue with brown algae, it blows off easily with baster, but re-covers corals fairly quickly. Is also on sand, glass and some rock. I have cut feedings way back and stopped feeding reef chili (was feeding every other day).
Nitrate is 0
Phos is .03
Tank is almost 3 months old.
Skimmer runs 24/7

 

[Reefer Matt]

Could be dinoflagellates or cyanobacteria. A microscope will help id which one so a treatment plan can be followed.