Sorry, I misunderstood your PO4 level and thought 0,015 instead of 0,15 you wrote.
Anyway, I think in a tank with NPS corals You do not use powerful light. So less risk to grow algae or any unwanted photsynthetic organism, as dino or cyano.
So I would appreciate an interpretation about triton recommendation to keep PO4 0,018ppm (using PO4 adsorber) in a system based on macroalgae.
Please remember they recommend NO3 1,6ppm, and 2/3 of total nitrogen should be nitrate (so not all that low). This should be the perfect recipe for growing corals, together with all other inorganics elements in the right concentration.
Luca