The immobilization of Spirulina maxima for tertiary treatment of diluted aeration-stabilized swine waste was investigated The technique employed for the immobilization was active entrapment in K-carrageenan. The entrapped cells were used for repeated batch-culture nutrient-removal. The immobilized algae were submitted to a number of repeated cycles for the effluent, seven or 10 days each, depending on the initial nutrient concentration of the swine waste. The ammonium nitrogen and total-phosphorus removal efficiencies were the same at 25% dilution of the swine waste and over 90%. For 50% dilution the removal efficiency for ammonium was over 80% and 90% for total-phosphorus