culture. If water turbidity is due to the presence of planktonic organisms (water is green in color), it is beneficial since it serves as food for tilapia and thus enhances growth. But if it is due to suspended silt or other solids, it would only suffocate the fish and will eventually result to mortality of stocks. The ideal level of turbidity is 1,300 mg/l or 25-35 cm visibility using secchi disc, below and above this level is a condition unfavorable for tilapia. Total Ammonia – the un-ionized ammonia is highly toxic to fish. The safe level of un-ionized ammonia is between 0.02 – 0.05 mg/l. Presence of too much ammonia in the pond water exhibits a pungent odor. High ammonia level can be avoided by avoiding overfeeding.

FEEDS AND FEEDING

Feeding Methods:Hand feeding (sabog) – Broadcast MethodUse of feeding bags/feeding trays – feeds are placed in B–nets (32mm mesh size) which are called feeding bags. The bags are tied in poles and they are suspended in pond water surface. Fish obtain feeds in the suspended bags by picking or suction.

Determining Average Body Weight (ABW), Daily Feed Ration (DFR) & Feed Conversion Ratio (FCR)1. ABW (g) = total weight of fish randomly sampled # of fish sampled2. DFR – the amount of feeds given daily = ABW x total number of stocks x feeding rate x survival rate3. TFR – total amount of feeds given for the whole culture period = DFR x feeding duration4. FCR = Amt. of feeds given during the culture period weight gain of fish (kgs)Ex.: Computation of daily feed ration (DFR) for 1,000 pcs fingerlings.1. ABW = 1,000 g = 50 g 20 pcs 2. DFR = 50 g x 1,000 pcs x 5% x 95% = 2,375 g or 2.375 kilos feeds

daily

FEEDING RATE AND SCHEDULE*

Days Types of Feeds

Feeding Rate

Feeding Frequency

Ideal Weight of Stocks

1 to 15 fry mash 8% of BW 4x a day 6g @ day 1516 - 31 fry mash 7% of BW 4x a day 25g32 - 46 starter 6% of BW 4x a day 36g47 - 61 grower 5% of BW 3x a day 50g62 – 76 grower 4% of BW 3x a day 72g

77 – 91 grower 3% of BW 3x a day 100g

92 – 105 finisher 3 to 2% of BW 2x a day 121g

106 – 120 finisher 2% of BW 2x a day 150gNote: The closer the FCR to 1.0, the better is the fish feed. Good feeds have an FCR ranging from 1 to 1.5*semi-intensive culture system

It is also recommended to apply fertilizer / chicken manure at the rate of 2000 kg/ha/month for chicken manure and 100 kg/ha/month for 16 – 20 -0 for the production of natural food for the fish. Fish Sampling should be conducted every month to monitor growth of the stocks.

HARVESTING Selective harvesting – it is usually done in undrainable ponds using gill nets, cast nets and seine nets. Total harvesting - ponds are totally drained and fish are confined in the catch basin where the fish are caught by seine nets.Do not feed the fish 24 hours before harvesting or transporting.

RECORD KEEPING

Among the important data to be recorded are: daily pond activities, operating cost which includes pond inputs, quantity and cost (fertilizer, fingerlings, pesticides etc.) production data, stocking, recovery and daily water parameters, ABW. Causes of failure and success can be traced from the records.

TILAPIAGROW-OUT

For more information, please visit or contact us:

Department of AgricultureBUREAU OF FISHERIES AND AQUATIC RESOURCES

Regional Office No. 02Carig, Tuguegarao City

Tel. No. (078) 304-4252 / 304-4261Telefax No. (078) 304-5331 / 846-3661

Email Address:bfar_ro2@yahoo.com

Please visit our website:http://region2.bfar.da.gov.ph/

SIMPLE COST ESTIMATE*(1,000 square meter fishpond project)

OPERATING EXPENSESLabor cost for pond preparation 900.00Farm implements (weighing scale, nets) 1,150.005,000 pcs size 22 fingerlings @ 25 cents /pc. 1,150.00Fuel used in hauling fingerlings & feeds 3,000.00(40 bags commercial feeds)2 bags fry mash/booster @ 810/bag 1,620.004 bags starter @ 790/bag 3,160.0020 bags grower @ 765/bag 15,300.0014 bags finisher @ 750/bag 10,500.0017 bags chicken manure @ 30kg/bag @ P 40 680.0035 kgs 16-20-0 @ 1,500/bag 1,050.0020 liters diesel @ 45/liter (water pump) 900.00Labor of caretaker @ 500/mo. x 4 months 2,000.00Hired labor during harvest 600.00Plastic bags and snacks for harvest 500.00Total production cost 42,510.00

INCOME STATEMENTProjected production (80% survival rate)--666.67 kgs @ P90/kg.Gross sales 60,000.30Less production expenses 42,510.00Net income 17,490.30ROI 41.14%

*semi-intensive culture system

SITE SELECTION

WATER SUPPLY – the site must be accessible to adequate water supply and free from contamination and pollution. Provide each compartment with an individual water inlet and drainage outlet. SOIL CHARACTERISTICS – clay, clay loam, and sandy loam soils are best for fishpond projects. Deposits of organic matter of about 16% are best for fishponds. Avoid sandy, rocky or stony soils because these do not retain water in the pond.POND COMPARTMENTS – area of grow-out ponds ranges from 1,000 -10,000 sq. m. per compartment, smaller compartments are easier to manage however it requires higher cost for development.DRAINAGE – take into consideration easy drainage to facilitate harvest and proper cleaning of the pond bottom when constructing the pond.Other factors to consider:

• Choose a flat terrain for easier excavation and leveling. • Avoid exposing the fishpond to strong winds which generate wave

action that destroys the sides of the dikes. • Construct a diversion canal along the perimeter dike for runoff

water during heavy downpour as protection from flood.

TYPES OF CULTURE SYSTEM

Extensive culture system- the growth of fish depends on the natural food present in the pond, which is produced through fertilization. No supplemental feed is given to the fish during the course of the culture period. The recommended stocking density of this kind of culture system is 10,000-20,000 pieces/hectare or 1 – 2 pcs/sq.m. Semi-intensive culture system- the fish depends on the natural food and supplemental feeds. In this system, the stocking density is 30,000-50,000 pieces/hectare or 3-5 pieces/sq.m.Intensive culture system- high stocking density and intensive feeding is required in this type of culture system. Some form of water movement and aeration is necessary to maintain the desired level of dissolved oxygen (DO) in the pond. Water quality monitoring is very important in this system to avoid water pollution that may affect the fish. In fishpond, the stocking density is more than 50,000 pieces/hectare or more than 5 pcs / sq.m

FISHPOND MANAGEMENT

POND PREPARATION - the following steps are necessary specially for old ponds:1. Total draining of fishpond – to eliminate old stocks, predators and

unwanted species such as catfish, mudfish, biya, ayungin 2. Pond poisoning – It is recommended to poison the pond, to be

sure that all predators and unwanted species are eliminated. If ponds cannot be drained fully, poison is applied by spraying /

broadcasting it all over the pond bottom with at least 3 to 5 cm of water. Recommended poisons are tobacco dust, rotenone (tubli) at 25 kg per hectare or a combination of lime and 21-0-0 (5:1), at rate of 3g per liter. Use of chemical pesticides is not advised as it will have residual effect on the pond and will also destroy soil quality.

3. Pond washing – pond washing is done to eliminate the effect of poison by letting filtered water come in and out of the pond.

4. Leveling / harrowing of pond bottom – the bottom of the pond is leveled to remove excess mud and dirt. It also facilitates harvesting especially during seining.

5. Sun dying of pond bottom – for old ponds, it is recommended to expose the pond bottom to sunlight and allow the soil to crack. Toxic gases evaporate and eliminates faster in a sun dried pond bottom.

6. Application of lime – if the pond becomes acidic, application of lime is recommended. The recommended rate is 100 g/sq.m. or 1,000 kg/ha. Soil samples can be submitted to the BSWM for analysis.

7. Screening of water inlet and outlet – before filling – in of water, fine mesh screen is installed in the water inlet to avoid entrance of unwanted species and at the water outlet to prevent escape of fish after stocking.

8. Filling-in of water – pond is ready to be filled-up with water to the favorable depth of 1.0 – 2.0 meters after screen is installed in the water inlets and outlets.

9. Basal fertilization – growth of natural food (plankton) in the pond is produced through basal fertilization. Organic fertilizer (chicken manure) is applied through broadcast method all over the pond at the rate of 1,000 - 2,000 kg/ha. In combination to chicken manure, inorganic fertilizer, 16-20-0 (Ammonium phosphate) is also applied at the rate of 100-200 kg/ha by hanging or platform method. This recommended rate may be increased or reduced depending on the amount of natural food is already present in the pond. Basal fertilization should be done one week before stocking. Presence of natural food can be determined through change in color of water into green or yellow green. Over-fertilization should be avoided as it will cause plankton bloom which could result to oxygen depletion. Ammonium phosphate will do if chicken manure is not available.

TRANSPORT OF FINGERLINGS – 20 x 30 inches x 0.003 gauge plastic bag is the most common container for fingerling transport today.

Below is the recommended quantity of fingerlings per bag:Size Quantity

Fry (0.01g ABW) 2,000 pcs/bag to 3,000 pcs/bagSize 24 2,000 pcs/bagSize 22 1,000 pcs/bagSize 17 500 pcs/bag

Size 14 300 pcs/bagReduce quantity for trips more than 6 hrs. It is also advised to place cracked ice on top of plastic container if temperature exceeds 30 ˚C. Buy or acquire fingerlings from reputable sources.

STOCKING OF FINGERLINGS

Acclimatization is done to avoid thermal shock that will cause mortalities on the fingerlings. This is done by letting the plastic container float in the pond for 10 – 20 minutes before releasing the fingerlings. Stocking is usually done early in the morning or late in the afternoon to reduce stress on the stocks. Make sure that fingerlings are acclimatized first before releasing it into the pond.

POND CARE & MAINTENANCE

Weed Control – growth of weeds such as kang kong and water lily in ponds affects the photosynthetic activity, thereby, reducing production of natural food. Excessive fertilization during pond preparation enhances the growth of aquatic weeds. Some fishpond operators are using grass carp as a means of biological control for weeds.

Water Management Some important water parameters to be monitored:Water Level / Depth – the water level should be maintained at 1.2 –2.0 meters. For semi-intensive culture management it is advisable to freshen water during the earlier months & change water (30% only) twice a month on the 3rd month and weekly on the last month. Water freshening should be made immediately if problems are observed on the tilapia stocks. Dissolved oxygen (DO) – low DO level would result to poor growth, disease outbreaks or mortality. Ideal DO level is 5 ppm. This can be maintained by avoiding excessive feeding and stocking.pH – indicates the hydrogen ion concentration, which determines the acidity or alkalinity of the water. At pH 6.5 to 9.0 fish thrives well and grows fast, below or above this range results to poor growth or mortality. pH level can be determined through laboratory analysis at BFAR. Temperature –The optimum water temperature favorable for growth of tilapia is 29 ˚C – 31 ˚C. The cold tolerant tilapia however can thrive in temperature as low as 15 ˚C.Salinity – freshwater tilapia can tolerate salinity up to 5 parts per thousand (ppt), beyond this amount is not desirable. Saline tolerant tilapia can tolerate salinity as high as 15 ppt to 25 ppt, this breed is usually cultured at brackishwater areas. Turbidity – the presence of suspended solids in the water contributes to the turbidity of water. These suspended solids include sediment particles, silt and organic matters (such as detritus, fecal materials and phytoplanktons). Turbidity can either be harmful or beneficial in tilapia