Composite Fish Culture

Fish & Aquatic Ecology Unit

Department of Zoology

Rajiv Gandhi University

EATING 100g FISH A DAY KEEP THE DOCTORS AWAY ……………

•World fish consumption -16.3Kg• Indian fish consumption – 9.0Kg

Why fish culture?

• Provides nutrition

• Provides income

• Provides employment

Where, fish culture?

• Low lying areas

• Perennial water source

• Accessibility

• Free from pollutants

Types of Culture

Monoculture

Polyculture

What is Composite fish culture?

Culture of different fast-growing and compatible species having different feeding habits, in the same pond is called “composite fish culture” or “polyculture” or “mixed farming”.

According to the depth, a pond can be divided in to three distinct zones

I. Upper surface zone

II. Middle column zone

III. Bottom zone

A particular species exploits a particular zone

Surface

Column

Bottom

Catla Silver carp

Rohu Grass carp

Mrigal Common carp

In this multi-species culture system, the fishes utilize all the ecological niches of the pond 1. Catla (Catla catla) – surface feeder

2. Rohu (Labeo rohita) – column feeder

3. Mrigal (Cirrhinus mrigala) – bottom feeder

4. Grass carp (Ctenopharyngodon idella) -

Feeds on macro-vegetation

5. Silver carp (Hypophthalmichthys molitrix) –

surface feeder

6. Common carp (Cyprinus carpio) – bottom

feeder

Surface feeders

Catla

Silver carp

Column feeders

Rohu

Grass carp

Bottom feeders

Mrigal

Common carp

Management of Composite Fish Culture Pond

Management practices

• Pre-stocking

• Stocking

• Post-stocking

Pre-stocking managementa) Weed clearanceWhy?• Aquatic weeds reduce the living space available

for fish• Prevents entry of sunlight into the pond• Consume nutrients from the pond – affects the

production of fish food organisms (plankton)• Provides shelter to fish enemies• Causes obstruction for harvesting of fish• Excessive growth – upsets oxygen balance

Unmanaged weed infested pond

Managed pond

b) Eradication of unwanted fish

Why?

• The unwanted fish compete for food, space and oxygen with the fingerlings of cultivable carps

• Some fishes may prey upon the carp fingerlings

How?

• Dewatering ensures complete removal of unwanted fish

• In ponds, where dewatering is not possible, mahua oil cake @ 2000-2500 kg/ha-m depth is recommended

Dry the pond until the bottom gets cracks. Help in eradication of unwanted and harmful micro-organisms, removal of some toxic gases from pond bottom, kill the parasites.

Unwanted fish for CFC

c) ManuringWhy?• Manuring ensures production of natural fish

food in the pond (phytoplankton & zooplankton)

How?• If mahua is applied, Raw Cow Dung (RCD)

should be applied 7 days after mahua application @ 5000 kg/ha

• If mahua is not applied, RCD should be applied @ 10,000 kg/ha, 15 days before the stocking of fish seeds

RAW COW DUNG (RCD)

d) Liming

• Liming is done after 7 days of RCD application

Why?

• Liming is done to correct the acidity

• It also helps to keep the pond hygienic

pH of soil Type of soil Dose of lime (kg/ha)

4.5-5.0 Highly acidic 2000

5.0-6.0 Moderately acidic 1200

6.0-6.5 Mildly acidic 1000

6.5-7.0 Near neutral 400

7.0-7.5 Mildly alkaline 200

Dose of lime for different soil types

Stocking

a) Stocking density

• A stocking density of 7500 nos. of fingerlings/ha is recommended

• A stocking density of 6000 fingerlings/ha would be ideal when the rearing period is limited to about 8-10 months

b) Species combination• In North Eastern Region, the species combination and

proportion depends on the altitude of the place• In lower altitudes (upto 2500 ft msl) with warm

temperature – 20% Catla : 20% Rohu : 15% Mrigal : 20% Silver carp : 10% Grass carp : 15% Common carp

• In medium altitudes (upto 3500 ft msl) - 20% Catla : 10% Rohu : 10% Mrigal : 30% Silver carp : 10% Grass carp : 20% Common carp

• In higher altitudes (above 3500 ft msl & below 4500 ft msl) - 40% Silver carp : 25% Grass carp : 35% Common carp

c) Stocking size

• Fingerlings of 100-150 mm size are ideal for stocking, particularly in the colder climatic conditions of NEH Region

Post-stocking management

a) Supplementary feeding

• Rice polish and mustard oil cake is fed to the fishes in a ratio of 1:1 by weight @ 3% of their body weight of fishes

• The feed can be adjusted by regular monitoring of food consumption from the feeding trays

• Feed is administered twice daily – morning and evening

• The feed ingredients – made a dough - placed in feeding basket

• For grass carp, chopped green vegetation are provided on feeding trays made of bamboo

• 10-15 trays will be required for a 1 ha. pond

• Aquatic and terrestrial vegetation including fodder grasses and vegetable wastes can be supplemented for grass carp

• Grass carp is fed at least 1hr prior to the feeding of rice polish+M.O.Cake

• Feed for the grass carp can be provided on a feeding tray (made of split bamboo in a rectangular form)

A view of the feeding basket

Feeding in progress

b) Fertilization

• Periodic organic and inorganic manuring is essential for production of fish food organisms in the pond

• Cow dung is applied as organic manure @ 1000 kg/ha/month.

• Urea @ 25 kg/ha/month and single superphosphate @ 30 kg/ha/month are applied as inorganic fertilizers

• The inorganic manure should be applied by mixing with mud to facilitate slow leaching

Mode of application of inorganic fertilizer

Inorganic manure is normally applied after 15 days of application of organic manure

Fertilization should not be done during cloudy weather and when algal blooms appears

c) Liming

• Liming is done once in a month @ 25 kg/ha (300 kg/ha/yr), two days after the application of organic manure

Mixing of lime

Application of lime

d) Raking

• Raking of pond bottom is done, a day after liming

• Raking can be done by netting or by dragging branches of tree or by a rope tied with bricks

• Raking helps in proper mixing of lime with the bottom sediment and also helps in the release of obnoxious gases trapped at the bottom

Growth and health care

• The growth and health of fish is to be regularly monitored by periodic netting, atleast once in two months

• If feed provided is not consumed, either the fish are suffering from some disease or the water quality is deteriorated

• Quantity of feed needs to be adjusted based on the growth increment of fish

• A bath in potassium permanganate solution is necessary for the netted fishes, before releasing back into the pond

Potassium permanganate bath for netted fish

Checking the growth of fish

• If managed properly, a fish production of 2000-3000 kg/ha/yr can be obtained, with a net profit of Rs.40,000-45,000/- can be expected

Harvesting and Production

Generally practiced for 12 months

Catla 800gm-1kg

Rohu 600-800gm

Mrigal 400-600gm

Silver carp 1.0-1.2kg

Grass carp 1.0-1.5kg

Common carp 800gm-1.0kg

Economics (12 months culture period in a 1ha pond)

SNo

Items Cost (Rs.)

A.Expenditure

1 Weed clearance 1,000.00

2 Mahua Oil Cake (2500kg @ Rs.4.50/kg)

11,250.00

3 Lime (1500kg@ Rs.6.00.kg) 9,000.00

4 Cow dung (20,000kg @ Rs. 30.00/Quintal)

6,000.00

5 Urea (250kg @ Rs.6.00/kg) 1,500.00

6 SSP (300kg @ Rs.5.00/kg) 1,500.00

7 Fingerlings (@7500 nos./ha) 15,000.00

8 Feed i) Rice bran (2625kg @ Rs.4.00/kg)

10,500.00

ii) M.O.C (2625kg @ Rs.7.00/kg)

18,375.00

9 Netting 2,000.00

10

Miscellaneous 5,000.00

Total Expenditure 81,125.00

B.Return

2500kg fish @ Rs.50/kg 1,25,000.00

C Profit (B-A) 43,875.00

Fish for healthFish for incomeFish for enjoymentFish for hobbyFISH FOR ALLGROW MORE FISH FOR A HEALTHY TOMORROW