Comparing filtration rates of silver carp and Daphnia magna in differentconcentrations of algae Scenedesmus quadricauda (solution for biological

For comparing filtration rates of silver carp and Daphnia magna in different concentrations of algae Scenedesmus quadricauda, pure algal species were prepared from the algae cultivation laboratory of Caspian Sea Ecological Research in the Mazandaran province, and was massly cultured in algae cultivation laboratory of Qaresou-Iran research station. There was 4 treatments ( 1%, 2.5%, 5% and 8 % body weight per 25 liters of water ) for silver carp feeding experiments and 3 treatments ( 4, 11 and 35 mg per liter ) for Daphnia feeding experiments and each treatment had 3 replications. During 24 hours, sampling was performed from fish aquariums and daphnia experiment flasks and the final concentration was calculated. Fish feeding experiment was repeated for three weeks. Daphnia feeding experiment was repeated for 10 days. Silver carp test results showed that with increasing concentration of algae, filtration rate reduced and ingestion rate increased. Daphnia test results also showed that with increasing concentration of algae, filtration rate and ingestion rate increased. Finally, due to higher filtration rate of Daphnia in comparison with silver carp in the high concentration of algae Scenedesmus quadricauda, it can be a more appropriate filter for this green algae.

Daphnia; Filtration rate; Silver carp; Scenedesmus quadricauda