Sea Bass Farming Excellence

Asian Sea Bass (Lates calcarifer) - The Premium Marine Finfish

Asian sea bass, known locally as "Modha", represents one of the most promising marine aquaculture species in Sri Lanka. With its rapid growth rate, high market value, and excellent meat quality, sea bass farming offers exceptional opportunities for commercial aquaculture ventures.

This euryhaline species thrives in both brackish and marine waters, making it ideal for diverse farming systems from coastal ponds to offshore cages. NAQDA provides comprehensive support for sea bass farmers, from hatchery-produced fingerlings to technical expertise and market linkages.

1kg

In 6-8 Months

Rs.800-1200

Per Kilogram

85%+

Survival Rate

High Export

Demand Globally

Culture Systems & Methods

Cage Culture

Floating & Fixed Cages in Coastal Waters

  • Cage size: 5x5x3m to 10x10x5m
  • Stocking density: 30-50 fish/m³
  • Deep water sites (>5m depth)
  • Good water circulation essential
  • Production: 20-30kg/m³
  • Investment: Rs.500,000-2M per cage

Pond Culture

Earthen & Lined Ponds

  • Pond size: 0.5-2 hectares
  • Depth: 1.5-2.5 meters
  • Stocking: 5,000-10,000/ha
  • Aeration required
  • Yield: 8-15 tons/ha/year
  • Lower investment costs

RAS (Recirculating)

High-Tech Indoor Systems

  • Complete environmental control
  • Stocking: 60-100kg/m³
  • Water reuse: 95-99%
  • Year-round production
  • Disease-free environment
  • High initial investment

Pen Culture

Enclosures in Natural Waters

  • Lagoons and estuaries
  • Low construction cost
  • Natural food availability
  • Area: 1,000-5,000m²
  • Tidal water exchange
  • Community-based farming

Raceway Systems

Flow-Through Concrete Tanks

  • Continuous water flow
  • High stocking density
  • Easy management
  • Grading facility
  • Quarantine capability
  • Nursery to grow-out

Nursery Systems

Fingerling to Juvenile Stage

  • Hapa nets in ponds
  • Indoor tanks (5-20m³)
  • 30-45 day rearing
  • Size: 2cm to 10cm
  • Intensive feeding
  • Critical stage management

Production Timeline

Month 0: Stocking

5-7cm fingerlings, acclimatization, initial feeding

Month 1-2: Nursery

Growth to 50-100g, 3-5% body weight feeding

Month 3-4: Juvenile

200-400g size, grading required, 2-3% feeding

Month 5-6: Grow-out

600-800g weight, market size approaching

Month 7-8: Harvest

1-1.5kg market size, selective harvesting begins

Optimal Water Quality Parameters

Parameter Optimal Range Critical Limits Monitoring Frequency
Temperature 28-32°C <26°C or >34°C Daily
Salinity 15-35 ppt 5-45 ppt tolerable Daily
Dissolved Oxygen >5 mg/L <3 mg/L critical Twice daily
pH 7.5-8.5 6.5-9.0 tolerable Daily
Ammonia (NH₃) <0.1 mg/L >0.5 mg/L toxic Weekly
Nitrite (NO₂) <0.5 mg/L >1.0 mg/L harmful Weekly
Transparency 30-40 cm <20 or >60 cm Daily
Alkalinity 80-150 mg/L <60 mg/L unstable Weekly

Feed & Nutrition Management

Feed Requirements by Growth Stage

Fry Stage (2-5cm)

  • Protein: 45-50%
  • Pellet size: 0.8-1.5mm
  • Feeding rate: 8-10% body weight
  • Frequency: 4-5 times/day
  • Live feed supplementation

Juvenile (5-20cm)

  • Protein: 42-45%
  • Pellet size: 2-3mm
  • Feeding rate: 5-7% body weight
  • Frequency: 3-4 times/day
  • FCR: 1.2-1.5

Grow-out (>20cm)

  • Protein: 38-42%
  • Pellet size: 4-6mm
  • Feeding rate: 2-3% body weight
  • Frequency: 2 times/day
  • FCR: 1.5-1.8

Alternative Feed Sources

Health & Disease Management

Vibriosis

Bacterial infection

Symptoms: Red spots, fin rot, lethargy

Prevention: Water quality, probiotics

Treatment: Antibiotics (with prescription)

VNN (Viral Nervous Necrosis)

Viral disease

Symptoms: Abnormal swimming, dark coloration

Prevention: Certified seed, biosecurity

Treatment: No cure, prevention critical

Parasites

External & internal

Types: Sea lice, anchor worms, flukes

Prevention: Quarantine, freshwater baths

Treatment: Formalin, copper sulfate

Biosecurity Measures

Economic Analysis

Production Cost

Rs.400-500

Per kilogram

Market Price

Rs.800-1,200

Farm gate price/kg

FCR

1.5-1.8

Feed conversion ratio

Profit Margin

40-60%

Net profit

ROI Period

18-24

Months

Annual Yield

20-30

Tons per hectare

Investment Breakdown (1 Hectare Pond)

Market Opportunities

Domestic Market

  • Hotels & restaurants: Premium segment
  • Supermarket chains: Fresh & frozen
  • Local markets: Whole fish sales
  • Value addition: Fillets, steaks
  • Growing middle-class demand

Export Markets

  • Singapore: Live fish trade
  • Maldives: Tourism sector
  • Middle East: Frozen products
  • EU markets: Certified organic
  • Premium pricing for quality

Video Tutorials & Resources

Learn sea bass farming techniques through expert guides

Sea Bass Farming Basics

Introduction to Asian sea bass culture

15:30

Hatchery Operations

Breeding and larval rearing techniques

18:45

Marine Cage Culture

Setting up and managing sea cages

20:15

RAS Technology

Recirculating aquaculture systems

22:30

Feeding Strategies

Optimal feeding for growth

14:20

Health Management

Disease prevention and treatment

16:40

Visit our YouTube channel for more sea bass farming tutorials and marine aquaculture content

Frequently Asked Questions

Why is sea bass considered a premium aquaculture species?

Asian sea bass (Barramundi) is highly valued for:

  • Premium market price - Rs. 800-1200/kg
  • Excellent meat quality - white, flaky flesh with mild flavor
  • Fast growth rate - reaches 500g in 6 months, 1kg in 12 months
  • High survival rate - 85-90% in good conditions
  • Strong export demand - popular in Asian and European markets
  • Versatile culture systems - ponds, cages, RAS
  • Year-round production capability
What are the different culture systems for sea bass?

Sea bass can be cultured in various systems:

  • Marine cages: Most common, 6-8 months grow-out
  • Brackish water ponds: Traditional method, 8-10 months
  • RAS (Indoor): High control, year-round production
  • Flow-through tanks: Coastal facilities
  • Floating net pens: Protected bays and lagoons
  • Integrated systems: With mangroves or other species

Each system has specific advantages depending on location, investment, and market requirements.

What are the key water quality parameters?

Optimal water conditions for sea bass:

  • Temperature: 26-32°C (optimal 28-30°C)
  • Salinity: 15-35 ppt (tolerates 0-45 ppt)
  • Dissolved oxygen: >5 mg/L (critical >4 mg/L)
  • pH: 7.5-8.5
  • Ammonia: <0.1 mg/L
  • Nitrite: <0.5 mg/L
  • Transparency: 30-60 cm

Regular monitoring and maintenance of these parameters ensures optimal growth and health.

What is the stocking density and production capacity?

Stocking densities vary by system:

  • Cages: 30-50 fish/m³ → 30-50 kg/m³ at harvest
  • Ponds: 5-10 fish/m² → 3-6 kg/m² production
  • RAS: 40-80 kg/m³ with proper management
  • Tanks: 20-40 kg/m³ flow-through systems

A 6x6x4m cage can produce 4-6 tons per cycle (8 months). Survival rates of 85-90% are achievable with good management.

What are the feed requirements and FCR?

Sea bass feeding program:

  • Fingerlings (5-20g): 48-45% protein, 6-8% body weight/day
  • Juveniles (20-100g): 45-42% protein, 4-5% body weight/day
  • Growers (100-300g): 42-40% protein, 3-4% body weight/day
  • Finishers (>300g): 38-40% protein, 2-3% body weight/day

FCR ranges from 1.2-1.8 depending on management. Feed costs represent 50-60% of production expenses. Use of fresh trash fish can reduce costs but requires careful management.

How long does it take to reach market size?

Growth timeline for sea bass:

  • Plate size (300-400g): 4-5 months
  • Standard market (500-600g): 6-7 months
  • Premium size (800g-1kg): 10-12 months
  • Export size (1.5-2kg): 14-16 months
  • Large size (>2kg): 18-20 months

Growth rates depend on temperature, feeding, and stocking density. Optimal temperature (28-30°C) can accelerate growth by 20-30%.

What are the common diseases and prevention measures?

Common health issues in sea bass farming:

  • VNN (Viral Nervous Necrosis): Vaccination, biosecurity
  • Vibriosis: Probiotics, water quality management
  • Sea lice: Freshwater baths, cleaner fish
  • White spot: Temperature control, reduced stress
  • Gill flukes: Formalin treatment, good water flow

Prevention through quarantine, vaccination, optimal water quality, and proper nutrition. NAQDA provides disease diagnostic and treatment services.

What is the market demand and pricing?

Sea bass market dynamics:

  • Local fresh market: Rs. 800-1200/kg whole fish
  • Hotels/restaurants: Rs. 1200-1500/kg premium grade
  • Export (frozen): $6-8/kg whole, $12-15/kg fillet
  • Live fish: Rs. 1500-2000/kg for high-end restaurants
  • Value-added: Rs. 2000-2500/kg (steaks, fillets)

Annual demand in Sri Lanka: 2,000+ MT with growing export potential to Singapore, Malaysia, and Middle East markets.

What is the investment required and profitability?

Economic analysis for cage culture (6x6x4m cage):

  • Cage setup: Rs. 400,000-500,000
  • Fingerlings (5,000): Rs. 150,000
  • Feed (6 tons): Rs. 900,000
  • Operating costs: Rs. 200,000
  • Total investment: Rs. 1.65-1.75 million
  • Production: 4-5 tons @ Rs. 900/kg
  • Revenue: Rs. 3.6-4.5 million
  • Net profit: Rs. 1.9-2.8 million per cycle
  • ROI: 115-160% per 8-month cycle
Can sea bass be cultured in freshwater?

Sea bass freshwater culture possibilities:

  • Juveniles can adapt to freshwater if acclimated gradually
  • Growth rate is 20-30% slower than in marine water
  • FCR increases slightly (1.5-2.0)
  • Requires harder water with minerals
  • Breeding requires return to saline conditions
  • Market acceptance may vary

While possible, marine or brackish water culture is recommended for optimal production. Inland saline water bodies can be utilized effectively.

What are the breeding and hatchery requirements?

Sea bass hatchery essentials:

  • Broodstock: 3-5 kg fish, 3+ years old
  • Spawning: Hormonal induction (HCG/LHRHa)
  • Fecundity: 200,000-800,000 eggs/kg female
  • Incubation: 15-20 hours at 28-30°C
  • Larval rearing: Green water technique with rotifers
  • Weaning: Day 25-30 to artificial feed
  • Nursery: 45 days to reach 2-3g

Hatchery success requires technical expertise, live feed culture, and precise environmental control. NAQDA hatcheries supply quality fingerlings.

How can I start sea bass farming?

Steps to begin sea bass farming:

  1. Site selection - protected bay, lagoon, or coastal pond
  2. Obtain NAQDA aquaculture license
  3. Environmental clearance from CEA
  4. Cage/pond construction or purchase
  5. Source quality fingerlings (5-10cm)
  6. Establish feed supply and storage
  7. Install monitoring equipment
  8. Stock and begin culture cycle
  9. Regular monitoring and maintenance
  10. Harvest and marketing arrangements

NAQDA provides training, fingerlings, technical support, and market linkages for new farmers.

Have more questions? Contact our sea bass farming experts:

Hotline: 1920 | seabass@naqda.gov.lk

NAQDA Support Services

Quality Seed Supply

Hatchery-produced fingerlings at subsidized rates

Technical Training

Comprehensive farming techniques and best practices

Financial Assistance

Loans and subsidies up to 50% of project cost

Disease Diagnosis

Free laboratory services and health management

Market Linkages

Connect farmers with buyers and exporters

Quality Certification

GAP and organic certification support

Start Your Sea Bass Farm Today