The Experimental Aquaculture Facility – showcasing Southern Hemisphere Atlantic salmon research using RAS
Hilder, PE and Carter, CG, The Experimental Aquaculture Facility - showcasing Southern Hemisphere Atlantic salmon research using RAS, 4th NordicRAS Workshop on Recirculating Aquaculture Systems Book of Abstracts, 12-13 October 2017, Aalborg, Denmark, pp. 32. ISBN 9788774812418 (2017) [Plenary Presentation]
Atlantic salmon farming in Tasmania has undergone significant expansion from 53 to almost 55,000 tonnes annual production in the last two decades. The industry injects $626.9 million to the Tasmanian Gross State Product and is the leading farming activity in Tasmania. The initial introduction of Atlantic salmon to Tasmania from the northern hemisphere meant that salmon were grown in some of the warmest waters in the world for Atlantic salmon. The industry now faces the climate change challenge to adapt farming practices to cope with higher summertime water temperatures. Along with industry, the Institute for Marine and Antarctic Studies (IMAS), University of Tasmania, recognised the urgent need for a purpose built research facility for large Atlantic salmon to provide practical solutions to manage environmental change and sustainability of production. The A$6.5 million Experimental Aquaculture Facility (EAF) was officially opened in 2015 using combined federal, state, industry and University funds. The University and the two industry partners, Skretting Australia and Huon Aquaculture, jointly manage the research and cover operational costs equally. We believe the EAF is the only saltwater RAS facility in the Southern Hemisphere capable of conducting research on large salmon (up to 5 kg). The facility comprises 14 saltwater RAS: 12 x 3200L individual RAS; 1 x 72,000L RAS (2 x 13,000L fish tanks); 1 x 178,000L RAS (12 x 7,000L fish tanks each with separate temperature control). EAF commissioning provided important empirical evidence of refinements necessary for Saltwater RAS. Primarily the elimination of nitrogen supersaturation as a result of air injection at a depth >1 m and the need for carbon dioxide removal to reduce chemical addition for pH control and the subsequent deleterious effects to fish because of high alkalinity. Each RAS system is equipped with sophisticated control including, gas control (oxygen, nitrogen and carbon dioxide), light control (photoperiod, intensity, fade up and fade down), parameter control (temperature, pH), feed control (delivery and recovery) and electronic system control (logging, remote control, alarm control, in tank live video feed). The high level of system control means the facility has the capacity to: mimic environmental variables that salmon would experience on farms, examine single or multivariate interactions on salmon growth and survival, develop Atlantic salmon RAS technology for optimal growth performance and model effluent outputs. The EAF has already achieved benefits with research outputs immediately integrated into commercial application.