We screened the bacteria with restoration and purification functions in lake water and found that,Bacillus subtilishad the highest water purification ability. Photosynthetic bacteria, lactobacillus bacteria, nitrifying bacteria and oligotrophic bacteria also showed different levels of lake water purification and restoration. L1873orthogonal experiments were designed to optimize the ratio of complex agents to get the best ratio of various bacteria as 10g/LBacillus subtilis, 2g/L photosynthetic bacteria, 0.8g/L lactobacillus, 0.6g/L nitrifying bacteria 1, 0.4g/L nitrifying bacteria 2 and 0.6g/L oli-gotrophic bacteria. When lake water was purified for 30 d under this ratio, total phosphorus content decreased 85.90%, total nitrogen content decreased 70.96%, and COD value decreased 81.19%.
 Z. Liu, W. L. Kingery and D. H. Huddleston, “Assessment of Water Quality Conditions in the St. Louis Bay Watershed,” Journal of Environmental Science and Health, Part A. Toxic/Hazardous Substances and Environmental Engineering, Vol. 43, No. 5, 2008, pp. 468-477. http://dx.doi.org/10.1080/10934520701796283
 J. A. Dittman, C. T. Drisco ll and P. M. Groffman, “Dynamics of Nitrogen and Dissolved Organic Carbon at the Hubbar d Brook Experimental Forest,” Ecology, Vol. 88, No. 5, 2007, pp. 1153-1166. http://dx.doi.org/10.1890/06-0834
 A. Pecharaply, A. P. Annachhatre and A. P. Parkpian, “Influence of Anaerobic Codigestion of Sewage and Brewery Sludges on Biogas Production and Sludge Quality,” Journal of Environmental Science and Health, Part A. Toxic/Hazardous Substances and Environmental Engineering, Vol. 42, No. 7, 2007, pp. 911-923.
 C. T. Frijters, M. Silvius and J. Fischer, “Applications for Both COD and Nutrient Removal in a CIRCOX Airlift Reactor,” Water Science and Technology, Vol. 55, No. 8-9, 2007, pp. 107-114. http://dx.doi.org/10.2166/wst.2007.248
 S. T. Lee, “Biodegration of Pyridine by Freely and Suspended Immobilized Pimelobacter,” Applied Microbiology and Biotechnology, Vol. 41, No. 6, 1994, pp. 652-657. http://dx.doi.org/10.1007/BF00167280