About this module
This module trains you to grow one crop of tilapia (and catfish) in a small earthen pond, from choosing the site to selling the harvest. You learn by doing: most of the time is spent at the pond, and every unit ends with a practical task and homework.
Who it is for. Beginners with no formal certificate. The level is National Proficiency I, where a trainee does routine tasks under close supervision.
The fish. Nile tilapia is the main farmed fish in Ghana. African catfish is often grown with it. Most facts here come from the CSIR Water Research Institute's farmers' manual for small-scale tilapia pond farming in Ghana.
This is not an accredited CTVET programme. No CTVET aquaculture package was found. The closest Ghanaian example is the Development Action Association's National Proficiency curricula in fisheries and fish processing, accredited by COTVET in 2018. This module follows CTVET's published format.
How the module works
Each unit has learning outcomes, performance criteria, the range and the evidence your assessor needs. You are judged Competent or Not Yet Competent by being watched at work, answering questions, and showing your logbook. About 70% of the time is practical, following CTVET's Oil Palm programme, which uses about 30% in school and 70% at the workplace.
Safety at the pond
Ponds can drown people, pumps can electrocute, and fish spines can infect cuts. Read this before you go to the pond.
- Never work alone at a deep pond, and keep a rope or float at the pond side. Drowning, falls, electric shock and bites are listed hazards of fish farming.
- Pumps and aerators: switch off and lock the power before anyone enters the water. Rubber boots do not protect you from electric shock. Keep well away from power lines; if a line falls into the pond, get out.
- Fish germs: some fish germs infect people through cuts and spine pricks. Wear gloves, cover cuts, and wash your hands. The Ghana manual also says wear gloves when handling fish.
- Lime and fertiliser burn skin and eyes: wear overalls, goggles, gloves and a mask when spreading lime.
Find your fisheries officer
Find out where the nearest Fisheries Commission or district fisheries office is and get a phone number. Write it in your logbook. You will need it in Units 1 and 6.
Unit 1 · Choose the site and get the permits
A pond is only as good as its water and its soil. Choose well and the rest is easier.
Competency standard
| Learning outcome | Performance criteria — the trainee… |
|---|---|
| 1.1 Check the water | checks the water source is year-round, clean and not polluted |
| 1.2 Test the soil | does field tests for clay content |
| 1.3 Check the land | checks slope, flooding and access; rejects wetlands and flood plains |
| 1.4 Know the permits | names the permits needed and who issues them |
Range. Rivers, streams, wells, springs and rain; earthen ponds. Evidence. Site report in the logbook; observation of soil tests; oral questions.
Water
The pond must be near water that lasts all year. The water should not smell or taste bad, or be milky, brown or very muddy.
| Source | Good | Bad |
|---|---|---|
| Spring | Steady temperature | Needs pumping |
| Well | No wild fish or predators | Low oxygen |
| River or stream | Cheap | Easily polluted; brings predators |
| Pipe-borne | Clean | Chlorine kills fish; costly; unreliable |
From the CSIR Tilapia Pond Manual. Many Ghanaian farmers chose a site just because water looked reliable, then found it dried up in the dry season.
Soil
The best pond soil has 20–35% clay; dykes need 30–35% clay or more. Never use topsoil in a dyke. Field tests from the manual include the squeeze-the-ball test and the mud-ball test: throw a moist ball of soil about 1 metre up and catch it; if it falls apart, it is too sandy; if it holds together, there is enough clay.
Land
Choose flat land with a gentle slope so the pond can drain. Do not build in a wetland or a river flood plain. Think about neighbours who use the same water, how close you are to buyers, and who owns the land.
Permits
Under the Fisheries Regulations 2010, a fish farm needs:
- an EPA environmental permit, then
- a Fisheries Commission aquaculture permit, and
- a Water Resources Commission water-use permit.
Small water users can be exempt from the water permit but must still register; taking water by hand is exempt altogether. The Ghana manual also mentions a District Assembly permit where local by-laws require one. Farms must keep records and send yearly data to the Fisheries Commission.
The law changed in 2025. The Fisheries and Aquaculture Act, 2025 (Act 1146) replaced the old fisheries law. Its permit details were not available. Ask the Fisheries Commission what you need before you dig.
Rate the site
Your trainer describes three possible pond sites. For each, list what is good and bad about the water, soil and land, and choose the best one.
Site survey
- With your group, walk the proposed site. Find the water source and note whether it flows in the dry season (ask locals).
- Dig to 50 cm in four places. Do the squeeze-ball and mud-ball tests on the soil from each.
- Look for signs of flooding: debris on trees, water marks.
- Write a site report: water, soil, slope, flood risk, access, and your verdict.
Visit a fish farm
Visit a fish farm near you. Ask where the water comes from, whether it ever runs dry, and what permits the farmer has. Write the answers in your logbook.
Unit 2 · Prepare the pond
A well-built and well-prepared pond holds water, drains when you want, and starts with no wild fish and the right soil.
Competency standard
| Learning outcome | Performance criteria — the trainee… |
|---|---|
| 2.1 Know the pond parts | names the dyke, inlet, outlet, overflow and screens, and what each does |
| 2.2 Lime the pond | measures pH; calculates and spreads the right amount of lime with PPE |
| 2.3 Fertilise and fill | applies cured manure at the right rate; screens the inlet and outlet; fills the pond |
Range. Earthen ponds, drainable and sunken. Evidence. Observation; lime and manure calculations in the logbook.
Size and shape
For small-scale commercial production, a pond should be at least 300 m²; rectangles are easiest.
| Part | Size | Source |
|---|---|---|
| Water depth | 0.8 m at the shallow end to 1.2 m at the deep end | CSIR Tilapia Pond Manual |
| Freeboard (dyke above water) | 30–50 cm | CSIR Tilapia Pond Manual |
| Bottom slope | 2 cm drop for every 10 m | CSIR Tilapia Pond Manual |
| Dyke slope | 2:1 if soil has 20–30% clay; 3:1 if less | CSIR Tilapia Pond Manual |
| Inlet pipe | 25–50 mm, at the shallow end | CSIR Tilapia Pond Manual |
| Outlet pipe | at least 100 mm, at the deepest end | CSIR Tilapia Pond Manual |
Screen the inlet, outlet and overflow so wild fish can't get in and your fish can't get out. Sunken ponds, fed by groundwater or rain, are the most common in Ghana.
Clean out, lime, fertilise
- Drain and dry the pond bottom for 1–2 weeks to kill wild fish.
- Lime by the pH of the soil or water:
| pH | Quicklime or hydrated lime | Agricultural lime |
|---|---|---|
| 4–5 | 150 g/m² | 200 g/m² |
| 5–6 | 100 g/m² | 150 g/m² |
| 6–6.5 | 60 g/m² | 100 g/m² |
| 6.5–7 | 20 g/m² | 40 g/m² |
| 7–9 | none | none |
Wear overalls, goggles, gloves and a mask; spread with the wind behind you; not on a rainy day; wait at least 24 hours before filling.
- Fertilise with cured manure to make the water green with tiny plants (food for tilapia): chicken or pig manure 50 g/m², cattle 100 g/m² to start; or NPK 15:15:15 at 5 g/m². Test that manure is cured: push a stick into the heap; if it comes out cold, it is ready. Don't lime and fertilise at the same time: lime locks up the fertiliser.
- Fill, with nets over the inlet and outlet, and keep the water in the pond at least 2 weeks before stocking.
Lime and manure sums
A pond is 20 m × 15 m. The soil pH is 5.5. (1) What is the area? (2) How much agricultural lime? (3) How much chicken manure to start?
Prepare the pond
- Help drain and dry the pond; remove mud and weeds.
- Measure the soil pH in several places.
- Calculate the lime, weigh it, and spread it with full PPE.
- After at least a week, test the manure is cured and spread the starting dose.
- Screen the inlet and outlet, fill the pond, and record dates and amounts.
Draw your pond
Draw your pond from the side and from above, with measurements. Label the dyke, inlet, outlet, overflow, screens, shallow end and deep end.
Unit 3 · Stock the fingerlings
Good fingerlings, stocked gently at the right number, are the start of a good harvest.
Competency standard
| Learning outcome | Performance criteria — the trainee… |
|---|---|
| 3.1 Choose fingerlings | knows where to buy and what size; explains why all-male tilapia |
| 3.2 Calculate numbers | works out how many fingerlings for the pond |
| 3.3 Stock gently | balances the temperature and lets fish swim out on their own |
Range. Tilapia and catfish fingerlings; earthen ponds. Evidence. Observation; stocking record.
Which fish and where from
- Ghana allows only local species and bans importing fish for farming; farmers use the Akosombo strain of tilapia, developed by CSIR's research centre at Akosombo.
- Buy from a hatchery or nursery with a Fisheries Commission certificate; check its name with other farmers and look at the fish and the hatchery's cleanliness. Selling fish seed without an FC certificate is not allowed.
- Buy fingerlings of 5–10 g.
Why all-male tilapia? Males grow about twice as fast as females, and females breed in the pond, filling it with small fish; young fish can end up as up to 70% of the harvest weight. All-male fingerlings are produced at the hatchery.
How many?
Stocking tilapia in a pond. The Ghana manual says 4–8 fingerlings per m². An IFPRI study gives 3–8 per m². FAO gives only 1–3 males per m² to grow them to 400–500 g. More fish means smaller fish at harvest and more risk of low oxygen. A beginner should start at the low end.
Catfish: 2–10 per m², giving about 500 g fish at 2 per m² or 200 g fish at 10 per m² after 6 months.
Stocking day
Stock in the early morning. Float the bag and mix pond water into it a little at a time so the temperatures match, then let the fish swim out by themselves. Remove any dead fish. In 2019, fingerlings lost on the journey averaged 11%, and 27% in the Ashanti Region: transport gently, early or late in the day.
How many fingerlings?
Your pond is 300 m². (1) How many tilapia fingerlings at 4 per m²? (2) If 10% die in transport, how many must you buy? (3) If they cost GH¢0.40 each, what is the cost?
Stocking day
- Count the bags and the fish (sample one bag to count).
- Float the bags, mix in pond water slowly over about 15–20 minutes.
- Let the fish swim out. Remove and count any dead.
- Record: date, time, number stocked, average weight, number dead, supplier.
Price check
Call or visit a hatchery or fish farm. Ask the price of tilapia fingerlings and their size. Write it down.
Unit 4 · Feed the fish
Feed is about 70% of the cost of growing fish in Ghana. Feeding the right amount, by weight, makes the money.
Competency standard
| Learning outcome | Performance criteria — the trainee… |
|---|---|
| 4.1 Choose the feed | picks the right pellet size and protein for the fish size |
| 4.2 Sample and calculate | weighs a sample of at least 30 fish; calculates the day's feed |
| 4.3 Feed and store | feeds at least twice a day; stores feed dry, off the floor |
Range. Floating pellets; tilapia and catfish. Evidence. Sampling and feeding records; observation.
Feed is the biggest cost
In a 2019 survey of Ghanaian fish farmers, feed made up 69% of the cost of production.
What size and how much protein
| Fish size | Pellet | Protein | Source |
|---|---|---|---|
| 1–5 g | 0.5–2 mm crumbles | 40–45% | CSIR Tilapia Pond Manual |
| 5–50 g | 2–3 mm | 40–45% under 20 g, then 38–40% | CSIR Tilapia Pond Manual |
| over 50 g | 3–6 mm | 33–35% at 100–250 g | CSIR Tilapia Pond Manual |
Catfish need 35–42% protein.
How much each day (tilapia)
| Average fish weight | Feed per day (% of total fish weight) |
|---|---|
| 15–30 g | 4.5% |
| 50–70 g | 3.3% |
| 100–150 g | 2.5% |
| 200–300 g | 2.0% |
| 400–500 g | 1.7% |
From the CSIR Tilapia Pond Manual (at 28 °C). Day's feed = number of fish × average weight × the %.
How to sample
Sample once a month, early in the morning before feeding. Weigh at least 30 fish together and divide by the number to get the average. Wear gloves, keep fish in water, and don't sample when the water is bad. Feed tilapia at least twice a day; fingerlings 3–4 times.
Storing feed
Buy only 4–6 weeks' supply. Keep it cool and dry, on pallets off the floor and away from walls. Use old bags first. Keep rats, insects and pesticides away, and throw away mouldy feed.
The day's feed
1,100 tilapia are in the pond. A sample of 30 fish weighs 3.6 kg. (1) What is the average weight? (2) Using the table, what % should you feed? (3) How much feed per day? (4) Split into two meals, how much each meal?
Feeding duty
- Each day, feed at the same times, scattering pellets where fish can reach them. Watch: if feed is left after 15 minutes, you are overfeeding.
- Record: date, times, kg fed, and how the fish ate.
- Once a month, help net and weigh a sample of 30 fish, and recalculate the ration.
- Check the feed store weekly; record stock and any mould or pests.
Feed price
Find the price of a bag of tilapia feed (any size) near you and its protein %. Work out the price per kg.
Unit 5 · Watch the water
Fish live in their water. When the water goes bad, fish stop eating, get sick and die. Checking it daily is the most important routine on a fish farm.
Competency standard
| Learning outcome | Performance criteria — the trainee… |
|---|---|
| 5.1 Read the signs | recognises gasping fish, bad colour or smell, and other warning signs |
| 5.2 Measure | measures temperature, pH and transparency (Secchi disc) and records them |
| 5.3 Act | takes the right action when oxygen is low or the water is too green |
Range. Earthen ponds; dawn and daytime checks. Evidence. Water records; observation; oral questions.
What good water looks like
| Measure | Acceptable |
|---|---|
| pH | 6.5–8.5 |
| Dissolved oxygen | above 3 mg/L |
| Temperature | 25–30 °C |
| Ammonia | below 0.03 mg/L |
From the CSIR Tilapia Pond Manual.
What temperature is best for tilapia? The Ghana manual gives 25–30 °C as acceptable. FAO says tilapia prefer 31–36 °C, and die at 11–12 °C or 42 °C. Southern Ghana's warmth suits tilapia either way.
Warning signs
Fish gasping at the surface, crowding at the inlet, slow growth, water too green or brown, bad smell, or very muddy water.
Low oxygen at dawn. Thick green water uses up oxygen at night, so oxygen is lowest just after dawn. If fish are gasping at dawn: stop feeding, add fresh water, and aerate if you can.
The Secchi disc
A black-and-white disc lowered on a marked rope. Note the depth where it disappears.
| Disc disappears at | What to do |
|---|---|
| under 25 cm | Too green: don't fertilise; watch for low oxygen; add water |
| 25–40 cm | Don't fertilise; watch the fish |
| 40–60 cm | Fertilise as normal |
| over 60 cm | Fertilise; maybe a bigger dose |
Advice from FAO. In Ghana in 2019, only 7% of pond farmers kept water records; half judged water only by colour and smell.
What would you do?
(1) At 6 am the fish are gasping at the surface and the water is dark green. (2) The Secchi disc disappears at 70 cm and the fish are growing slowly. (3) The water smells bad and there is uneaten feed on the bottom.
Daily water round
- At dawn, walk round the pond: are fish gasping? Record yes or no.
- Measure and record temperature and pH once a day.
- Take a Secchi reading twice a week and record it.
- Report any warning sign to your trainer at once.
Make a Secchi disc
Make a disc from a plate or lid about 20 cm across, painted in black and white quarters, tied to a string marked every 10 cm. Bring it to class.
Unit 6 · Keep fish healthy and safe
Most fish disease starts with stress: bad water, crowding, rough handling. Prevent stress, spot sickness early, and keep predators and thieves out.
Competency standard
| Learning outcome | Performance criteria — the trainee… |
|---|---|
| 6.1 Spot sickness | names signs of sick fish; removes and buries dead fish |
| 6.2 Prevent disease | follows biosecurity: clean tools, known inputs, limited visitors |
| 6.3 Protect the pond | keeps dykes trimmed; keeps animals and predators away |
Range. Tilapia and catfish; earthen ponds. Evidence. Health record; observation; oral questions.
Stress and signs of sickness
Stress comes from bad water, pollution, poor feed, crowding, predators, germs, and handling. Signs of sick fish: erratic swimming, gulping air, crowding at the inlet, rubbing on walls, not eating, bulging eyes, wounds, swollen belly, cotton-like mould on the skin.
In 2018 a virus (ISKNV) killed 60–90% of tilapia in some cage farms on Lake Volta. Report any disease to your fisheries or extension officer. The Fisheries Commission can stop fish being moved from an area with an outbreak.
Biosecurity
Buy inputs only from known, certified sources; set one entry point for visitors and vehicles; disinfect tools; keep sick fish apart; and remove and bury dead fish quickly.
Predators and thieves
Birds, snakes, frogs and lizards eat fish. Keep grass on the dykes short so snakes, frogs and rats can't hide, keep cattle and goats away, and don't plant big trees near the pond. Use nets and scaring rather than killing wild animals.
Name the sign
Your trainer gives you eight descriptions of fish behaviour. For each, say if it is a sign of sickness or stress, and what you would check first.
Health and pond round
- Each day, watch the fish for 5 minutes at feeding time; record anything unusual.
- Remove dead fish, record the number, and bury them away from the pond.
- Once a week, cut the grass on the dykes and check the screens.
- Clean and dry nets and buckets after use.
Predator watch
Watch your pond (or any pond) for 30 minutes at dawn or dusk. List every animal you see near the water, and which ones could eat fish.
Unit 7 · Harvest and sell
The harvest is the payday. Plan the buyer before you net the first fish, and keep the fish fresh.
Competency standard
| Learning outcome | Performance criteria — the trainee… |
|---|---|
| 7.1 Plan the harvest | finds buyers first; stops feeding 1–2 days before |
| 7.2 Harvest | uses nets and draining to harvest; sorts fish by size |
| 7.3 Keep fresh and record | keeps fish clean, cool and off the ground; records weight and sales |
Range. Partial and total harvest; selling fresh or on ice. Evidence. Observation; harvest and sales record; profit sum.
When and how big
A crop in a Ghanaian pond usually takes 6–7 months. Ghana's market grades tilapia by size, from "economy" (100–200 g) and "regular" (200–300 g) up to size 4 (over 800 g). Catfish reach 200–500 g in about 6 months, depending on how many were stocked.
Partial or total harvest?
A partial harvest lets you sell to order, but stresses the fish left, keeps you feeding, and invites theft. A total harvest avoids those problems. Tilapia escape nets, so a full harvest needs netting and draining.
Harvest day
Stop feeding 1–2 days before. Use seine, cast and scoop nets, and sort fish by size. Kill fish quickly, use clean water and containers, keep fish off the ground, and sell them alive or on ice, or smoke, salt or dry them.
Smoking safely: traditional Chorkor and drum smokers can leave smoke chemicals in fish far above EU limits; the improved FAO-Thiaroye kiln stayed within them, and charcoal is cleaner than wood.
Money
Net profit = total sales − total costs. Return on investment = net profit ÷ total costs × 100. In 2019 Ghanaian pond farmers averaged a cost of about GH¢8.76 per kg and a farm-gate price of about GH¢12 per kg. Prices have risen since; use today's prices.
Profit sum
A pond stocked 1,200 fingerlings; 90% survived to 300 g. (1) How many kg harvested? (2) At GH¢30 per kg, what are the sales? (3) If costs were GH¢6,000, what is the profit and the return on investment?
Harvest day
- Help find and book buyers before harvest.
- Stop feeding 2 days before.
- Net the pond, then drain to catch the rest. Sort by size.
- Weigh each size group; keep fish in shade, on ice or alive.
- Record kg per size, price, buyer, and total sales.
Market survey
At a market, record the price of fresh tilapia and catfish by size, and of smoked fish. Who are the buyers and sellers?
Glossary
| Term | Meaning |
|---|---|
| Biosecurity | Everything you do to keep disease out |
| Competent / Not Yet Competent | The two possible results of a CBT assessment |
| Dyke | The earth wall around a pond |
| Fingerling | A young fish, a few grams in weight, for stocking |
| Freeboard | The height of the dyke above the water |
| Inlet / outlet | Where water comes in / goes out |
| Lime | Powder that makes acid soil and water less acid |
| Secchi disc | A black-and-white disc for measuring how green the water is |
| Stocking density | Number of fish per m² |
| All-male tilapia | Tilapia fingerlings that are all males, so they grow faster and don't breed |
Logbook
Copy these pages into an exercise book. Your logbook is part of your assessment evidence.
- Unit 1: site report; soil test results
- Unit 2: pH readings; lime and manure sums and dates
- Unit 3: stocking record
- Unit 4: daily feeding; monthly sample weights and new ration; feed store check
- Unit 5: dawn checks; daily temperature and pH; Secchi readings
- Unit 6: daily health notes; dead fish counts
- Unit 7: harvest weights; sales; profit sum
- Every homework, dated
Self-check quiz
- Name three things a good pond site needs.
- What clay % is best for pond soil?
- Which permits does a fish farm need?
- Why stock all-male tilapia?
- How many tilapia per m² does the Ghana manual suggest?
- How do you work out the day's feed?
- How many fish do you weigh in a sample?
- Fish are gasping at dawn. What do you do?
- The Secchi disc disappears at 20 cm. What does that mean?
- Name three signs of sick fish.
- What do you do with dead fish?
- Why must you never enter a pond with the pump switched on?
Further reading and sources
Best next reads: the CSIR-WRI Farmers' manual on small-scale tilapia pond farming in Ghana; the Fisheries Commission's current permit guidance; FAO's catfish and tilapia notes.
What this module does not cover: cage farming on lakes, hatchery work, building concrete tanks, treating diseases with drugs (a job for officers and vets), and Ghana-specific catfish guidance (FAO figures are used).
Every source used in this manual is listed, with links, in the Teacher Copy.