World Aquaculture - December 2014

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26 DECEMBER 2014 • WORLD AQUACULTURE •
located in Kubu, Bali raises specific pathogen-free L. vannamei in
ponds, applying basic biofloc technology with no water exchange.
Ample aeration and well-controlled dissolved oxygen concentration
maintained good water quality in the culture environment. The farm
has produced 45-55 t/cycle since 2009 in a stable and sustainable
way from 12 small concrete ponds with a total surface area of 2
ha (Taw and Setio 2014). The technology also has been applied in
super-intensive raceways production as high as 9.9 kg/m2 (Samocha
et al. 2012) and 7.5 kg/m3 (Otoshi et al. 2006).
The technology was applied for other species of shrimp, such as
P. monodon in Australia by CSIRO in 2008 and freshwater prawn
Macrobrachium in India. It has also been applied in blue shrimp
L. stylirostris broodstock production (Cardona et al. 2014). That
study compared two culture systems, clearwater and biofloc, and
confirmed that biofloc is beneficial to the reproductive performance
of blue shrimp broodstock and larval quality.
Biofloc Technology and Biosecurity
With emerging viral problems and rising costs for energy,
biosecurity with biofloc technology appears to be an answer for
sustainable production (Table 4). Large shrimp farms, which
initiated biofloc technology in Sumatra, Indonesia from late 2002 to
2007, have not experienced any WSSV outbreaks (Taw 2010).
As at other farms in the vicinity, Arca Biru shrimp farm,
Blue Archipelago Berhad was faced with serious outbreaks from
white spot syndrome virus (WSSV) before the redesign. During
its first new cycle, viral incidents were common in the vicinity. On
one occasion, dead WSSV positive shrimp were found within the
main supply canal. Despite this, the production cycle was a success,
without viral outbreaks (Taw et al. 2011)
A large-scale “integrated shrimp aquaculture park” (iSHARP)
project started by Blue Archipelago Berhad in Malaysia in 2009 had
a goal to complete over 600 ponds and reservoirs for raising Pacific
white shrimp on 1,000 ha of land at Setiu, in the state of Terengganu,
northeast of Kuala Lumpur. The first stocking was initiated in
October 2011. A total of 144 ponds were in operation by mid-
November 2012. No incidents of white spot syndrome (WSSV) or
early mortality syndrome (EMS) have been reported at the facility
(Taw et al. 2013) (Fig. 6).
The small family-owned shrimp farm located in Bali referred
to previously has produced shrimp continuously since 2009 in a
stable and sustainable way without WSSV and IMNV outbreaks
(Taw and Setio 2014).
TABLE 1. Basic management concepts in shrimp culture. TABLE 3. Comparative performance and technical
features of intensive biofloc and greenwater systems
for shrimp.
TABLE 4. Biosecurity attributes of biofloc systems.
TABLE 2. Desired concentrations of select water
quality variables in biofloc systems applied to
commercial shrimp farming.
VARIABLE VALUE NOTE
Salinity 20-35 ppt
Temperature 25-30 C
DO > 4.0 mg/L
pH 7.3-8.4
Alkalinity > 70 mg/L as CaCO3 tends to reduce with
duration of culture
period
TAN < 1.5 ppm higher than
autotrophic system
NH3-N < 0.1 ppm higher than
autotrophic system
Nitrate (NO3) < 5.0 ppm higher than
autotrophic system
PO 4-P < 2.0 ppm