A comparative study of reducing the percentage of ammonia and nitrates in stellate sturgeon (Acipenser stellatus) farming effluents by Hediste diversicolor, Gamarus (Gammarus aequicauda) and reed plants (Phragmites australis)

The attention to the control of aquatic ponds and the optimum use of water consumption can reduce pollution of the environment and maintenance ecological conditions of the region. This study investigated the effect of artificial wetlands on the reduction of ammonia and nitrate factors and also physical and chemical changes loading in wastewater to improve water efficiency in stellate sturgeon ponds over a ten-month growth period. To conduct this research, 5 ponds (4 m-2) and 5 cement canals were used. Three fiberglass ponds were used to culture of stellate sturgeon under the same conditions, two fiberglass ponds were used for culturing of Hediste diversicolor and Gammarus (Gammarus aequicauda) larvae, and cement channels were used to establish reed plants (Phragmites australis) in the treatments in the first to third rows, respectively. At this study was used 50% recyclution water and 50% freshwater. The ammonia and nitrate factors were measured in all ponds monthly. In the output of the reed plant, the highest percentage of ammonia (NH3-N) and nitrate (NO3-N) removal was related to the water that was passed through the gammarus ponds and stellate sturgeon, respectively. The results of percentage reduction of wastewater nutrients among the treatments showed that the highest ability to remove ammonia (15.6%), and nitrate (24%), was observed in the ponds of Phragmites australis and it also economically plays an important role due to the lack of food cost for feeding worms and Gamarus.