Cyanobacteria and their associated bacteria have also been successfully used in wastewater treatment. For example, cultures of Oscillatoria sp. BDU 30501, Aphanocapsa sp. BDU 16 and a halophilic bacterium Halobacterium US 101 were used to treat a factory effluent and resulted in reduction of calcium and chloride to levels that did not inhibit survival and multiplication of fish (Uma and Subramanian 1990). Phormidium valderianum BDU 30501 was used to reduce phenol concentrations (Shashirekha et al. 1997) while Oscillatoria boryana BDU 92181 was used to eliminate melanoidin pigment from distillery effluents (Kalavathi et al. 2001).