stubborn algae

ive had an issue with gha since i bought the rock in my tank. i have a 2lf phosban reactor, a coralife 220g skimmer, 2 k425 nanos, and a hob carbon filter. ive been dosing with api algae fix for a few weeks. i dropped my light cycle to 4-5 hrs a day. i also cut my feedings down alot. i no longer feed flake because of all the phosphates. my bioload is small. 2 smaller clowns a yt damsel and a coral banded shrimp i just got. i bought my light fixture in oct. i believe. the lights are the only thing i can think of besides the fact that i dont rinse the food after it thaws. any ideas? cyno is coming in now too

 

and my levels were all 0 besides nitrates which were.005 ppm i believe ill have to get my book. ph was 8.3 sg was 1.025 temp stays around 77-78