215
12.6 Ongrowing
12.6.1 System Requirements and Management
In flow-through open seawater systems, cylindrical tanks of any size can be used.
The same tanks used in the nursing phase can be continually used for ongrowing
(Nabhitabhata 1978; Nabhitabhata and Nilaphat 1999). In closed seawater systems,
two rectangular raceways of 65,000-L volume are used for ongrowing (Minton
et al. 2001; Barord et al. 2010). Each raceway is equipped with its own pre-filter
tank, airlift and a shared filtration tank. The water is pumped by airlifts from the
pre-filter tank into the filtration tank at a flow rate of 228 L min
−1
before returning
to the raceway. The tank volume can be exchanged five times daily. Another set of
raceway used has a capacity of 16,000 L with a flow rate of 90 L min
−1
. The pharaoh cuttlefish can be cultured through three consecutive generations in this system
(Minton et al. 2001).
The density during the ongrowing phase is adjusted to correspond to the tank
volume and water system used (Table 12.2). In a flow-through seawater system,
Anil et al (2005) transferred 30-day-old cuttlefish (approximate 20 mm in mantle
length and 1.9 g in weight) from 60-L fibreglass tanks to 500-L tanks where the
density is decreased from 1,000 to 100 individuals m
−3
. After 90 days when the
cuttlefish grows 59 mm in mantle length and 34 g in weight, they were transferred
Fig. 12.4 Growth in terms of the relationship between weight (g) and age (d). Arrows indicate
approximate age at mating (m) and spawning (s). (After Nabhitabhata and Nilaphat 1999;
Nabhitabhata 2002)
12 Sepia pharaonis
12.6 Ongrowing
12.6.1 System Requirements and Management
In flow-through open seawater systems, cylindrical tanks of any size can be used.
The same tanks used in the nursing phase can be continually used for ongrowing
(Nabhitabhata 1978; Nabhitabhata and Nilaphat 1999). In closed seawater systems,
two rectangular raceways of 65,000-L volume are used for ongrowing (Minton
et al. 2001; Barord et al. 2010). Each raceway is equipped with its own pre-filter
tank, airlift and a shared filtration tank. The water is pumped by airlifts from the
pre-filter tank into the filtration tank at a flow rate of 228 L min
−1
before returning
to the raceway. The tank volume can be exchanged five times daily. Another set of
raceway used has a capacity of 16,000 L with a flow rate of 90 L min
−1
. The pharaoh cuttlefish can be cultured through three consecutive generations in this system
(Minton et al. 2001).
The density during the ongrowing phase is adjusted to correspond to the tank
volume and water system used (Table 12.2). In a flow-through seawater system,
Anil et al (2005) transferred 30-day-old cuttlefish (approximate 20 mm in mantle
length and 1.9 g in weight) from 60-L fibreglass tanks to 500-L tanks where the
density is decreased from 1,000 to 100 individuals m
−3
. After 90 days when the
cuttlefish grows 59 mm in mantle length and 34 g in weight, they were transferred
Fig. 12.4 Growth in terms of the relationship between weight (g) and age (d). Arrows indicate
approximate age at mating (m) and spawning (s). (After Nabhitabhata and Nilaphat 1999;
Nabhitabhata 2002)
12 Sepia pharaonis