Telapia Culture/ Production Technique Part: 02

Pond preparation:

Soil sampling:

For pond bottom preparation, soil samples are collected from the pond bottom and the dikes for pH and organic matter content analysis. Soil pH analysis is generally conducted to determine lime requirement. Soil samples are collected in a S or X-shaped pattern and only the top soil 0-15 cm is taken as sample to determine soil quality.

Step of pond preparation

Drying: 

It is done by drain out water completely from pond bottom and exposing to air and remain for sun burn (2-3 weeks) until the pond soil become cracks. It helps-

       To release toxic gases. Remove Vibrio and Pseudomonas species pathogen bacteria.

·         Remove undesirable species and harmful substances

·         Oxidize mineralized nutrients and increase decomposition rate

·         Remove predators.

·         Excess organic matter tends to lead anaerobic (O₂- deficiency) condition in pond bottom. Drying pond bottom turns it aerobic (O₂- increase) condition.

·         Change sediment from black to brown.

Control of undesirable species:  

Undesirable species are those which compete for space, food and oxygen with culture stock. Undesirable species are-Pest, predators, competitors.

Controlling method: Two types 1. Physical and 2. Chemical

Physical method: completely drying, incoming water passing through screening, by trapping.

Chemical method:  Two types of chemicals are used such as Organic chemic- Rotinone, Saponin and inorganic chemicals- calcium carbide, tobacco dust.

Tilling:

 Tilling or ploughing of  bottom soil improves soil quality. Tilling the upper 5–10 cm of soil is most important. It has others advantages-

·         speeding up the oxidation process

·         Release of nutrients that are locked in the soil.

·         Eradication of predators in the sub-surface layer

Liming : 

Liming is the application of calcium and magnesium compounds to the soil for the purpose of reducing soil acidity and also for increasing water transparency.  If water become turbid it  affect on gill and eye of fish as well as create hindrance for growing  natural phytoplankton. Water transparency should be 25 cm for maintaining high pond productivity.

Calcium oxide (CaO), Calcium hydroxide, Ca (OH)₂  and [CaMg (CO₃)₂]  and CaCO₃  are liming substances. Liming can be done in three different ways:

Liming

·         by broadcasting

·         by mixing with water and spraying                                

·         by liming the water flowing into the pond.            

It used for

·         Grow biological productivity

·         If apply in water increase light penetration

·         Reduce BOD

·         Control predators

·         Increase soil fertility

·         Neutralize the acidity of soil.

Application :

 (1 decemel or 1 shotangsho = 40 Square meter= 435 square feet)

 ( 100 shotangsho = 4046 Square meter)

• For pond bottom preparation you have to used  1.5-2 kg light lime Per decimal / shotangsho. Muddy soil is a little bit acidic that's why for increasing water alkalinity extra lime is used.
• For reducing water turbidity 1.5-2 kg lime or Gipsum1-2 kg is used, it ultimately increase pond productivity.

Fertilization :  

 After 5-7 days of liming, it is best for both organic and inorganic fertilization…………..

Urea and TSP basically used for increasing natural productivity in pond .

Application:   

   150-200 gm      Urea       Per Decimel / shotangsho

   100 gm      TSP      Per Decimel / shotangsho           
   50 gm   MOP     Per Decimel / shotangsho                
   5- 7 kg    Cow dung  Per Decimel / shotangsho

                                                   

Water management

After 3-4 days water management should be started

·         Screening (3 layers, 60 mesh size) out water before fulfilling pond.

·         Spray crustracide (Ripcot) on the dike and slope to remove and kill the crustacean from the pond surrounding area.

·         Use high concentrated KMnO4 solution in each entrance for disinfection before entry of anything.

·         Use fencing net around the pond so that any kind of undesirable species cannot entry in pond.

·         Per 100 shotonsho/decimel use 5-10 kg molasses, 5-10 kg Rice bran, and 50-100 gm yeast powder if possible 200 gm pH Fixer mixed in water wait  2-3days and apply its juice everyday up to 7 days continuous for growing good plankton in pond water for better survival. .

·         After preparation of pond water ideal condition will be

·         pH 7.5-8.5

·         Alkalinity  120-150ppm          

·         Greenish color

·         Transparency will be 25-30 cm

·         DO = > 5-8 mg/L·
   NH₃₌ 0 , H₂S=0, I-=0, NO₃=0

Telapia-culture-production-technique part 03