Vinny, I probably have 5 different types of algae, bryopsis, bubble, hair, turf. Other assorted types, I'm collecting it

Tank is almost 2 years old, almost no sand left, PO4 <0.04, NO3 higher, maybe 20ppm, I can't get it down.
All media removed, photo period reduced on both main lights and actinics, food input almost zero for 3 weeks. Skimmer remained online, filter sock for mechanical removal. Dosed 21ml every other evening for 3 weeks. No impact at all on any type of algae. Didn't even slow it down.