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- Production is consistent. Annual production exceed 12
tons/hectare/pond
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- Production is not consistent and sometimes fails on production
due to outbreaks of disease or low water and soil pH.
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- Prawns have good texture healthy color and less
"Blue-ness".
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- Some prawns have tail rot, shell disease, papery in texture
and more "Blue ness".
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- Annual rainfall in coastal regions of Malaysia often exceeds
1600mm. And with monthly average of 130mm. HDPE Liner ponds, can
be washed and cleaned in any weather. The disinfected ponds
immediately can be restocked without "Sun-drying"
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- Washing and cleaning of earthen ponds normally are hindered by
wet and moist days. "Sun-drying" is not possible in
monsoon period. Fallow period is always extended and restocking
is affected.
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- Less hydrogen sulfide layer forms at pond bottom. Bottom
clean, as sediment is discharged out during water exchange, less
anaerobic toxic bacteria accumulate at pond bottom. Balanced
ecosystem is conductive for healthy growth and is
"Environmental-friendly".
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- More hydrogen sulfide layer is formed at pond bottom enhanced
with more anaerobic toxic bacteria. Black bottom layer affects
pond ecosystem and the results slow growth for prawns. The
accumulated sediment causes pollution to coastal sea.
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Contamination of sulfuric
Acid and Soluble Iron |
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- HDPE Liner pond prevents acid sulfate soil from contamination
of pond water. Pond water pH always is in optimum range.
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- Seepage of sulfuric acid and soluble iron contaminate the pond
water. Low pH and high iron results "stress" to
prawns. Slow growth with "yellow gill" during raining
season is very common in acid-sulfate mangrove soil.
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- Culture of plankton can be easily maintained as not no
contamination of sulfuric acid and toxic elements from the soil.
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- Bloom of "useful" plankton is succeeded by
Oscillatoria-a "blue-green algae". Healthy growth is
affected.
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- HDPE Liner prevent soil erosion on soil embankment from pond
wave action. Embankment is solid and strong and maintenance cost
is low.
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- Embankment of earthen pond subject to pond wave action that
causes erosion on the embankment and the maintenance cost is
higher.
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- Disease free and production consistent. Investment risk is
lesser.
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- High investment risk due to unforeseen problems of disease outbreaks.
Investment return is lower.
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- Less application of medicine, lime and other drugs. Good
FCR,
production cost is lesser than that of earthen pond.
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- Use more lime, medicine, PSB, enzymes and other additives. FCR
and production cost is higher.
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- HDPE Liner ponds prevent growth of brushes and grasses. Animal
predators and upkeep cost are lesser
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- Growth of brushes is an anchorage for predators, such as
reptiles and otters. Upkeep cost is higher.
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- HDPE Liner pond is very suitable for
prevention of white-spot virus infection in a close system
operation in which water exchange is minimized.
- Spread of white spot virus by crabs can
be prevented as the smooth surface of the liner is too slippery
to enable the crabs to climb up the pond.
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