A Novel Artemia Dispenser for Larval Fish Culture

Artemia (brine shrimp) are frequently used as a food source during the rearing of juvenile fish species. However, manually dispensing Artemia is labor intensive and inconsistent, while fully automated Artemia dispensing systems can be cost prohibitive. This paper describes the design, construction, and evaluation of a low-cost and easily-fabricated Artemia nauplii dispenser used during the early rearing of larval fish in a recirculating aquaculture system. The gravity-fed drip dispenser was constructed from polyvinyl chloride components and was designed to deliver a consistent supply of Artemia for six hours. During actual operation, the feeder performance was greatly influenced by the hatched Artemia slurry viscosity, clogging from unhatched cysts, and flow rate control mechanisms. Instead of the six-hour goal, feeding only occurred for three hours under optimal conditions. Despite these limitations, using this feeder proved beneficial by extending Artemia availability to larval fish for a longer period of time than manual feeding. The feeder integrated well with existing hatchery infrastructure. Modifications to improve feeder reliability and accuracy included replacing a push-lock fitting with a series of vinyl tubing segments, adding a dripline irrigation valve, using a salt buffer prior to adding Artemia to lessen slurry viscosity, and thorough removal of unhatched cysts and eggshells to prevent clogging.