“…No release was observed in the final clarifier. A literature search showed that “luxury uptake” of phosphorus occurred in several plants in the USA and India but those were all high‐rate plants with limited or no nitrification (Levin & Sharpiro, 1965; Milbury et al, 1971; Srinath et al, 1959; Vacker et al, 1967; Yall et al, 1970). The author concluded that the release of phosphorus in the second anoxic zone resulted from anaerobic conditions in that zone.…”