International Journal of Aquaculture, 2013, Vol.3, No.21, 117
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125
http://ija.sophiapublisher.com
118
removal, infiltration, gas balancing, oxygenation, and
disinfection. By addressing each of the key water
concern through treatment rather than flushing as is
used in flow-through and the partial reuse systems,
ultimate control over culture conditions and water
quality is provided. Deborah and Andrew
(1997)
concluded that indoor recirculating aquatic systems
may be used for various operations, some of which
may include: the quarantine of new animals, isolation
of sick fish, aquaculture, research, or as educational
displays.
In order to realize the full potential of agriculture in
Africa there is an urgent need to develop and promote
agriculture technologies that will intensify production
through the application of renewable energy systems.
Photovoltaics energy and electricity was used to
power the recirculating systems. The use of
recirculating systems will help to improve fingerling
production, renewable energy will serve to encourage
eco-friendly, economically and socially viable
aquaculture. The use of electricity in Nigeria is not
feasible as a result of constant power failure and
unsteady electricity supply. There is need to try
alternative energy sources as result of perennial
problem of power in our country since recirculating
system will not function properly where power is not
steady. Effort was made in this work to compare
electricty and photovoltaics productions.
1
The Objectives of This Project Were to
Assess the production and the growth parameters of
Clarias gariepinus
cultured in recirculating system;
Assess the effect of the use of energy sources
(
photovoltaics and electricity) in recirculating system
for fish production; Determine the water quality
parameters of recirculating system using biofilters and
UV light.
2
Results
As shown in Table 1, the results of the microbial analysis
for the water samples were (2.2×10
3
±200) cfu/ml,
(6.8
×10
3
±10)
cfu/ml and
(1.8
×10
3
±10)cfu/ml for
solar powered pump water, electric powered pump
water, and UV treated (outlet water) respectively. The
inlet water had no aerobic mesophilic bacteria. There
were no
Escherichia coli
in any of the water samples.
The total count show the number of organisms
recorded while the sensitivity tests conducted showed
the type of the organism identified was non
pathogenic only aerobic mesophilic bacteria were seen
as shown above. Inlet water had no fungus and no
aerobic mesophilic bacteria were seen in the inlet
water. Water from the electric powered pump
recirculating system had the highest average aerobic
mesophilic bacteria of (6.81×10
3
±10)
cfu/ml followed
by solar powered pump water which had
(2.2
×10
3
±200)
cfu/ml
aerobic mesophilic bacteria
count total. The lower microbial count for the solar
powered pump water could be due to the fact that the
solar powered pump is not restricted by power
shortage and therefore with continous flow, the water
flows freely and is recirculated unlike the electric
powered which is restricted by light and might be
stagnant during power shortage. Treated water had the
lowest aerobic mesophilic bacteria present. This is an
indication that the UV is effective in controlling the
microorganism that might be in the system which
might result in the disease outbreak in the system.
Table 1 Results of microbial analysis of the water samples in the recirculating system of solar and electric powered fish pond
Micro-organism
Bore hole (inlet water )
Solar powered pond
Electric powered pond
UV treated water
Total Mesophilic (Aerobic
bacteria) Count (cfu/mL)
Nil
2
×10
3
± 200
6.8
×10
3
±10
1.8
×10 ±10
Identified Microbes
No E. coli present
No E. coli present,
Klebsiella aerogenes
organisms present
No E. coli present, Klebsiella
aerogenes organisms present
No E. coli present,
Klebsiella aerogenes
organisms present
Table 2 shows the results of the physicochemical
properties for the different water sample. pH values
were 6.4±0.8, 6.9±0.17, 6.2±0.01, 8.0±0.01 for inlet,
solar powered pond, electric powered pond and UV
treated water respectively. pH values recorded shows
that the highest pH values was in UV treated water
with the value 8.0±0.01, followed by 6.9±17 in solar
powered fish pond, the least was 6.2±0.01 in electric
powered fish pond. Oxygen values were for inlet,
solar powered pond, electric powered pond and UV