Help Wanted : Algae Bloom

[Peter Peng]

My tank has been up for around 2 and a half months.
I have a skimmer and a phosban reactor running biopellets right now

I have a purple tang, and 5 anthias

I feed mysis usually 2 - 5 times a day due to my anthias

I have my lights on for 12 hours a day

Phosphates around 1ppm and nitrates 1 - 2

Ive been getting lot of this algae on the sand and on the rocks, none on the glass

Im not sure how to remove it so any help will be appreciated

I think its Dinoflagellates