Abstract: The deterioration of water quality is a common but troublesome problem in turtle cultivation. Beneficial micro organisms like PSB,NB and YULEI were used in turtle cultivation with sand bed in greenhouse. The results show that those micro-organisms could efficiently decompose pollutants in the pond sediment,and eliminate organic substances,COD,NH ₃-N and NO₃ ^- -N from the waterbody,thus reducing aquicultural and environmental risks,and water consumption as well due to their water purifying effect.

Key words: microbial technology, nitrifying bacteria, PSB, turtle cultivation, water purification