A laboratory-scale recirculating aquaculture system for juveniles of freshwater pearl mussel Hyriopsis (Limnoscapha) myersiana (Lea, 1856)

Growth and survival rates of juvenile freshwater pearl mussels Hyriopsis (Limnoscapha) myersiana (Lea, 1856) were compared at 0–120 days when reared in two closed recirculating aquacultural systems. System I was composed of a glass aquarium with a filter cabinet (combination of pebbles, ground freshwater mussel shells and nylon fiber), a UV tube, a resting cabinet, and a plastic culture unit. The system II was composed of 5 cabinets: a particulate filter cabinet, a macrophyte (Limnophila heterophylla) filter cabinet, a biological filter cabinet, a water resting cabinet and plastic culture units. Water flowed through the juvenile culture units at 20 ml/min in both systems. In each system juveniles were stocked at day 0 with sand at