If purple phototrophic bacteria (PPB)-based systems are to become a reality for resource recovery, research must be performed outdoors, using scaled reactors. Here we present the results from an outdoors 10 m long PPB-enriched flat plate photobioreactor (PBR), with a volume of 0.95 m 3. Results show that, over a long period (192 days), the PBR was able to effectively remove volatile fatty acids (VFAs), N, and P, with average removal efficiencies of >90%, 34-77%, and 28-45% (despite varying environmental conditions and a changing influent). Nutrient removal was limited by the availability of COD (i.e., VFAs). Operating anaerobically under a semicontinuous/day-only feeding regime, estimated biomass productivities of 6-24 g VS•m-2 •d-1 were achieved, with soluble COD removal rates up to 1.0 g•L-1 •d-1. Optimal conditions led to a relative PPB abundance of 0.56, at a minimum HRT of 2.1-2.4 d (1.0-1.2 d during day-only feeding). Biomass was harvested at ~90% VS/TS, with a crude protein content of 58% and an amino acid profile suitable for feeding purposes.