biomass production and ammonia and nitrite removal from fish farm effluent by scenedesmus quadricauda culture

ammonia (nh3) and nitrite (no2) toxic chemicals which resulted from fish culture, especially in intensive fish culture systems. to evaluate the efficiency of green algae scenedesmus quadricauda in ammonia and nitrite removal from intensive fish farm effluent and also its application as suitable culture medium for s. quadricauda , effluent water samples were collected from rainbow trout farm. six different treatments including diluted effluent with and without bbm, raw effluent with and without bbm, and concentrated effluent with and without bbm were prepared from fish farm effluent as culture medium for s. quadricauda. results showed that s. quadricauda could growth and reproduce well in examined treatments of fish farm effluent and ammonia and nitrite rates decreased in high levels (approximately 90 %).the maximum obtained biomass (0.99 g/l), number of algal cell (90.4 x 105 cell/ml), chlorophyll a (2.89 mg/l), removal percentage of ammonia (89.57 %) and nitrite (89.53 %) were obtained in diluted effluent with bbm (l+bbm).on the base of results of this research it seems that this algae could be used for ammonia and nitrite removal as well as algal biomass production for treatment of fish farm effluent before entering to natural environment. in addition, fish farm effluent could be used as suitable medium for algal mass culture.