when my phophates were at .21 I started running gfo through a reactor and have had great results. I am down to .08 now. I run a gfo reactor with BRS GFO.
There are several ways to reduce phosphate, including phosphate binders (like the GFO in chemipure elite), growing macroalgae, algal turf scrubbers, organic carbon dosing, and increased skimming. I use all of these except ATS.