YANG ET AL.: CULTURE EXPERIMENTS OF LOLIGO OPALESCENS 



Lamps 



1 meter 



Cooling 

 units 



'w///;;////////////////;/////;////////////////////////////?/ 

 Length x Width x Depth (m) 



A = 1.8x1.2x0.5 



B = 1.2 x 0.5 x0.3 

 C = 1.8 (diameter) x 0.8 

 D = 6.1 x2.4 xO 9 

 E = 1.8x0.6x0.6 



Protein skimmers 



Filter module 

 (4 particle + 2 carbon) 



Ultraviolet 

 sterilizer 



Figure 1.— Raceway (RW) system (L.O. 1982) with recirculating culture seawater (17,000 L total) for grow-out of juvenile and 



adult squid. 



In L.O. 1981, 129 squid were not transferred from 

 the CT tank and they continued to grow in the CT, 

 thereby allowing comparisons of temperature toler- 

 ance and survival in small versus large culture 

 systems. 



Natural seawater and artificial sea salts (Instant 

 Ocean) dissolved in deionized water were used in CT 

 systems for L.O. 1982 and L.O. 1981, respectively, 

 and artificial seawater was used exclusively in the 

 RW system in both experiments. Salinity was main- 

 tained between 34 and 37°/<x>. Trace elements were 

 supplemented regularly with Wimex Trace Ele- 

 ments. Temperature was maintained at 15°C unless 

 otherwise noted. The pH was maintained between 

 7.8 and 8.2, and low pH was corrected by the 

 gradual addition of sodium bicarbonate. 



Temperature and salinity were measured daily, 

 pH every other day, and metabolic waste products 



(ammonia, nitrite, and nitrate) were measured week- 

 ly. Ammonia-nitrogen levels were determined by the 

 Solorzano method (Strickland and Parsons 1972), 

 and nitrite-nitrogen was determined by the Shinn 

 method (applied to seawater by Bendschneider and 

 Robinson in Strickland and Parsons 1972). Nitrate- 

 nitrogen levels were determined using a prepacked 

 Hach reagent kit. 



Various live food organisms were fed to the squid 

 several times daily throughout the experiments. 

 Live planktonic organisms such as zooplankton 

 (mainly copepods) and small mysidacean shrimp 

 (Mysidopsis almyra) were the primary foods dur- 

 ing the first 60 d in the CT system. Brine shrimp, 

 Artemia salina; larval red drum, Sciaenops 

 ocellatus; and mysis stage penaeid shrimp were fed 

 as supplemental foods. Food organisms were added 

 to the CT system four or five times daily. Thereafter 



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