Case Study A

Tilapia fish farming in floating water cages is one of the fastest-growing aquaculture systems in Nigeria, particularly around the Lagos Lagoon. The lagoon provides stable water exchange, ideal temperature ranges (26–30°C), and natural plankton that supports fish growth and reduces feed costs.

The Case Study is based on 1 standard floating cage unit with partition, stocked with 1,000 tilapia juveniles, grown to market size over 5–6 months. Tilapia has high market demand in Lagos due to its mild taste, affordability, and suitability for grilling, frying, and processing.

• Produce one ton of table-size catfish within 6 months.

• Maintain healthy and stable pond conditions through regular monitoring.

• Implement a consistent, efficient feeding program.

• Reduce losses by using size grading to control cannibalism.

• Achieve predictable profit margins within a single production cycle.

3.1 Pond Types Used

Synthetic (Tarpaulin) Ponds — Primary System

• 2 units, 5 ft × 10 ft × 4 ft

• Water capacity: approx. 10,000 litres each

• Easy to install, maintain, clean, and disinfect

• Suitable for high-density stocking
  
  

Earthen Pond (Optional System)

• Natural soil environment with groundwater seepage

• Offers natural food (zooplankton), better buffering of water quality

• Lower feed conversion ratio (FCR)

• Suitable for farmers with access to land and flowing water
  
  

3.2 Water Quality Requirements

We maintain the following water conditions:

• Temperature: 26–30°C

• pH: 6.5–8.5

• Dissolved Oxygen: Minimum 4 mg/L

• Ammonia: Kept low through proper feeding and water exchange

• Transparency: 30–50 cm
  
  

3.3 Water Management Plan

• Regular water exchange (weekly), or flushing for cages

• Avoid overfeeding to reduce ammonia buildup

• Aeration/agitator use when oxygen drops

4.1 Stocking Strategy

• 1,000 catfish juveniles, ~8–10 g (8 cm size)

• Stock during cool hours (morning/evening)

• 15–20 minutes acclimatization before release

4.2 Feeding Schedule (Bag-Based)

The catfish are fed floating pellets 2–3 times daily, starting with small sizes and progressing to larger pellets as the fish grow. Over the 6-month cycle, a total of 75 bags (1,125 kg) of floating feed is used.

The feeding progression is as follows:

• Starter Feed (0.8–1.5 mm):
  Used during the first two weeks after stocking. A total of 2 bags is used to support early growth and help juveniles adapt to the new environment.
  
  

• Early Juvenile Feed (2 mm):
  Introduced after the fish settle, typically from weeks 2 to 4. About 5 bags are used during this phase.
  
  

• Juvenile to Grow-out Transition Feed (3 mm):
  Used from week 4 to around week 8 as biomass increases. A total of 13 bags is consumed.
  
  

• Grow-out Feed (4 mm):
  This size covers a major part of the cycle when the fish are actively growing. 20 bags are fed during this period.
  
  

• Pre-finisher Feed (6 mm):
  Used as the fish reach 400–700 g. Another 20 bags are required at this stage.
  
  

• Finisher Feed (9 mm):
  Fed during the last 4–6 weeks to bring fish up to an average of 1 kg. A total of 15 bags is used for finishing.
  
  

Across all stages, feeding quantities are adjusted based on fish appetite, behaviour, and body weight sampling. The cumulative feed supports steady growth from juvenile size to a target average weight of 1 kg per fish at harvest.

4.3 Feeding Rates

• 3–5% of biomass (months 1–3)

• 2–3% of biomass (months 4–6)
  
  

4.4 Sorting (Grading) Schedule

Sorting reduces cannibalism and supports even growth:

• Week 2: Remove early shooters

• Week 4: Control size variation

• Week 8: Major sorting (300 g vs small sizes)

• Week 16: Remove advanced growers (600–700 g)

• Week 20: Final grade before finishing

Cost & Revenue Financial Model (Cat Fish Pond – 1,000 Fish) - VIEW

6.1 Key Buyers

• Pepper-soup restaurants

• Grills and barbecue spots

• Local markets

• Smoked-fish processors

• Neighbourhood frozen shops

• Live-fish traders
  
  

6.2 Sales Channels

• Pre-orders before harvest

• Direct pickup from farm

• Delivery for bulk buyers

• Harvest-to-order for restaurants
  
  

6.3 Price Positioning

• Based on size, live weight, and season

• Discount for bulk buyers

Higher pricing for pre-booked restaurant buyers

The project includes a simple but effective risk management framework.

7.1 Operational Risks & Controls

1. Low Oxygen / Poor Water Quality

Risk:
Hot weather, waste buildup, overfeeding, or stagnant water can reduce oxygen levels and stress the fish.

Mitigation:

• Carry out regular water exchange or flushing.

• Reduce feeding when fish show slow response.

• Use aeration or agitation during low-oxygen periods.

• Avoid overstocking and remove waste promptly.

2. Cannibalism / Size Variation

Risk:
Catfish grow at different speeds; larger ones may prey on smaller ones if not sorted.

Mitigation:

• Perform regular grading every 2–4 weeks.

• Separate shooters (fast growers) early.

• Maintain adequate feeding rates and reduce feed competition.

3. Pond Damage / Structural Failure

Risk:
Tears, leaks, or weak joints in synthetic ponds can cause fish escapes or water loss.

Mitigation:

• Use reinforced tarpaulin or HDPE materials.

• Inspect pond edges weekly for weakness or sharp objects.

• Repair small tears immediately before they worsen.

4. Disease & Stress

Risk:
Dirty water, overcrowding, or poor handling can trigger infections and slow growth.

Mitigation:

• Maintain clean water through scheduled flushing.

• Avoid handling fish unnecessarily.

• Use salt baths or basic pond treatments when needed.

• Remove dead or weak fish promptly.

5. Feed Price Increases

Risk:
Floating feed prices can rise unexpectedly, increasing production cost.

Mitigation:

• Buy feed in bulk when prices are stable.

• Maintain at least 2 suppliers.

• Track FCR to reduce waste and improve efficiency.

6. Predators (Birds, Snakes, Frogs)

Risk:
Predators may enter the pond, injure the fish, or eat juveniles.

Mitigation:

• Use protective netting over the pond.

• Keep the farm area clean and free of vegetation.

• Seal pipe inlets and drainage points.

7. Theft / Vandalism

Risk:
Unauthorized access or night-time interference, especially in remote locations.

Mitigation:

• Use community monitoring and visibility.

• Employ night security where needed.

• Keep ponds close to occupied buildings or busy paths.

8. Flooding / Heavy Rain

Risk:
Overflows or flooding during the rainy season can damage ponds and cause escapes.

Mitigation:

• Build proper drainage channels around the pond.

• Maintain high pond walls.

• Avoid feeding during storms to reduce stress.