Effects of copepod density and water exchange on the egg production of Acartia tonsa Dana (Copepoda: Calanoida) feeding on Rhodomonas baltica

In this study, the objective was to investigate the effect of different copepod densities and the water exchange rate day-1 on the egg production of Acartia tonsa feeding on Rhodomonas baltica. It was a main task to find the best conditions for a maximum egg production in a large scale production system. The egg production under 3 different copepod densities (5, 8-10 and 20-53 ind/ml) and with water exchange rates of 100 and 500 % day-1 were tested. In addition, other variables like ammonia, temperature (20 °C), pH (8), salinity (24-34 ), dissolved 02 (> 5 mg/L) were measured and controlled if possible. Hatching success, female ratio, eggs per female and different consumption tests were measured.