Preliminary evaluation of a raceway photobioreactor for mass culture of microalgae for Peruvian scallop, Argopecten purpuratus postlarvae

Rafael Octavio Crisóstomo-Gamboa^1,2Renzo Pepe-Victoriano^1,3*Sheda Méndez-Ancca^1,2,4Jordan I Huanacuni^1,2,5Mario Ruiz-Choque⁴Abel Walter Zambrano-Cabanillas⁶Olegario Marín-Machuca⁶Obert Marín Sánchez⁷Carlos Enrique Chinchay Barragá⁸María del Pilar Rojas Rueda⁹Olger Acosta-Angulo^1,10,2Edgardo Cruces¹¹

• ¹Facultad de Recursos Naturales Renovables, Universidad Arturo Prat, Iquique 1110939, Chile., Iquique, Chile
• ²Programa de Magíster en Acuicultura, Mención en Cultivos de Recursos Hidrobiológicos y Mención en Acuaponía, Facultad de Recursos Naturales Renovables, Universidad Arturo Prat, Arica 1031597, Chile., Iquique, Chile
• ³Núcleo de Investigación Aplicada e Innovación en Ciencias Biológicas, Facultad de Recursos Naturales Renovables, Universidad Arturo Prat, Iquique 1110939, Chile, Iquique, Chile
• ⁴Departamento de Ingeniería Pesquera, Facultad de Ingeniería y Arquitectura, Universidad Nacional de Moquegua (UNAM), Ilo 18601, Perú., Moquegua, Peru
• ⁵Finfish Aquaculture Sociedad Anónima Cerrada, Tacna 23004, Perú., Tacna, Peru
• ⁶Faculty of Oceanography, Fisheries, Food Sciences and Aquaculture, Academic Department of Aquaculture, Environmental Sustainability Research Group (GISA), Federico Villarreal National University, Lima, Peru
• ⁷Academic Department of Medical Microbiology, Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima 15081, Peru, Lima, Peru
• ⁸Professional School of Food Engineering, Faculty of Pesquera and Food Engineering, National University of Callao, Callao 07011, Peru, Callao, Peru
• ⁹Escuela de Medicina Humana, Universidad Norbert Wiener, Lima, Perú;, Lima, Peru
• ¹⁰National University of Saint Augustine, Arequipa, Arequipa, Peru
• ¹¹Centro de Investigaciones Costeras, Universidad de Atacama (CIC-UDA), Avenida Copayapu 485,Copiapó 1530000, Chile, Copiapó, Chile

Feeding microalgae during the larval and post-larval stages of bivalve molluscs is necessary to overcome the high mortality rates that occur during metamorphosis. Proper selection of the microalgae species and strain to be used by considering its nutritional value, cell density, culture time, and type of culture system to improve bivalve productivity is of high importance. In this study a microalgae recirculating culture system was evaluated. The system consisted of an open horizontal photobioreactor inside a hatchery raceway tank (12 m long, 2 m wide, and 0.5 m high) with a central division of 10 m and a driving paddle that generated a continuous flow of water at a speed of 1.25 m/s. The microalgae species cultivated in the photobioreactor were strains of Nannochloris spp. and Phaeodactylum spp., with the former reaching a significantly higher cell density of 19.37 ± 1.31 (10 6 cell mL -1 ) than the latter, which obtained a cell density of 1.41± 1.31 (10 6 cell mL -1 ). The reproductive cycle for Nannochloris spp. was 59 d, whereas that for Phaeodactylum spp. was 19 d. This study demonstrates that, although both strains of species of microalgae can be cultivated utilizing a horizontal photobioreactor system in hatcheries, Nannochloris spp. strains offer productive advantages including culture duration.