Effective eutrophication control, especially for decentralized wastewater treatment, has received increasing attention in recent years. In view of this, iron oxide coated sand (IOS) granules, a recycled waste product from the drinking water industry, was investigated for phosphorus removal from goat farm wastewater, both at laboratory-scale and at full-scale. Brunauer-Emmett-Teller adsorption revealed a high specific surface area (249 m²/g) of the IOS. Fourier Transform Infrared Spectroscopy and X-ray Diffraction demonstrated that Fe(III) compounds are the main functional component and Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy showed that Fe and O elements covered more than 84% of the surface of the IOS. The IOS granules showed good phosphorus adsorption capacity over a wide pH range during laboratory-scale batch tests. Moreover, the phosphorus adsorption was very fast and the residual phosphorus concentration dropped below 0.02 mg/L within an hour at a dosage of 20 g/L. After adsorption, the exhausted IOS could be regenerated by using 0.5 M KOH, and more than 80% adsorption capacity remained. Laboratory-scale column tests with real wastewater originating from a goat farm were run and Bed Depth Service Time and Bohart–Adams models were applied in view of scale-up. Based on this, a full-scale IOS based fixed bed reactor was designed, built and tested at a goat farm. A TP removal efficiency of 99% with a 0.87 m³ IOS fixed bed reactor (fed at 2.2 m³/d) was obtained. The TP concentration in the effluent remained below 0.3 mg/L for nearly 400 days, achieving long term TP removal. This study demonstrates that IOS based treatment is an ecological and environmentally friendly method, suitable for full-scale (decentralized) wastewater treatment.