Ghana farms two fish, and each is a separate business. Nile tilapia is the volume crop, grown in cages on Lake Volta; African catfish is a smaller, hardier trade with its own live market. For both, the quality of the fingerling you start with matters most. Seed is the main bottleneck, and the shortage of good seed is one of the clearest openings in the sector.
Nile tilapia is the leading farmed species at about 89,850 tonnes in 2023, and African catfish is second at about 25,600 tonnes.1 Tilapia is what most people mean when they talk about fish farming in Ghana.
It grows in floating cages, it is sold fresh, and its economics are set on Lake Volta. The lake, mostly through floating cages, supplies about 90 percent of Ghana’s farmed tilapia and catfish.2 African catfish is the second, smaller business. It is hardy, it breathes air, it survives in poor water that would kill tilapia, and it is sold live or smoked rather than fresh. The two share feed suppliers and policy, but they need different skills, sites and buyers. A common mistake for new entrants is to treat them as one crop.
Nile tilapia (Oreochromis niloticus)
African catfish (Clarias gariepinus)
The fingerlingHealthy, uniform fingerlings beside weak, uneven ones. Seed quality has a large effect on whether a batch survives its first weeks.
What this means. Choose between tilapia and catfish by the market you can reach. Tilapia is a fresh-fish, high-volume cage business, and its profit depends on feed cost and disease. Catfish is a hardy niche business, sold live or smoked, and it copes with poor water and small budgets. The two need different skills, sites and buyers.
GIFT grows faster in trials; Akosombo, the only approved improved strain, copes better with low oxygen and heat.
Speed is one factor of severalWithin tilapia, the legal choice is narrow. Akosombo is the only improved strain approved for farming in Ghana, and GIFT has entered only through research trials and illegal imports.34 GIFT is faster: in a pond trial at the CSIR Water Research Institute, GIFT reached about 150 grams against about 85 grams for the selected Akosombo line and about 68 grams for an unselected Akosombo control line, and the authors estimate GIFT grows 1.6 to 1.9 times faster than the selected line.5
Speed is one of several things that decide whether a cage of fish reaches harvest. The native Akosombo strain, bred at Ghana’s own research institute, is tougher. In laboratory tests it tolerated low oxygen better than GIFT and had a higher median lethal temperature, about 45.1 against 41.5 degrees Celsius.4 Both lethal temperatures are far above the 23 to 31 degrees Celsius recorded on Lake Volta farms,6 so on a crowded lake, where oxygen can fall sharply overnight, low-oxygen tolerance is the more useful advantage. In the same trial, survival to harvest was only about 53.6 percent and did not differ significantly between GIFT and the Akosombo lines.5
MARKET SIGNAL: CERTIFIED SEED IS SCARCE. The law also matters here. Importing live fish for aquaculture without Fisheries Commission approval is an offence under the Fisheries and Aquaculture Act, 2025 (Act 1146), and illegally sourced GIFT broodstock is one possible route by which the 2018 virus reached Lake Volta; the ornamental fish trade is another.7 A farmer who can supply certified, disease-screened Akosombo seed meets a clear market need, and one the regulator wants to see filled.
Ghana’s hatcheries produced about 382 million fingerlings in 2024, below the 544 million the Ministry targeted,8 and seed quality and availability are now the main reason tilapia output has stagnated.9 In a survey of 30 farms on Lake Volta, about 63 percent had sourced broodstock or fingerlings from a farm that tested positive for the virus.6
Two things follow. First, seed is scarce, so a farmer often cannot get the quantity, size or strain they planned for, when they planned for it. Second, seed moves disease: in the Lake Volta survey, one farm with high virus positivity supplied broodstock or fingerlings to 17 other farms.6 A supplier of clean seed would tackle both the shortage and the spread of disease.
Sources: Ministry of Fisheries and Aquaculture Development; Ministry of Fisheries and Aquaculture.108
Hatchery output fell from about 615 million fingerlings in 2022 to about 381 million in 2023 and 382 million in 2024, below the Ministry's targets in both later years.
Seed moves diseaseGood seed and good stocking follow a few practical benchmarks that decide whether a batch survives its first weeks. Farmers chasing the cheapest seed often skip them.
Getting monosex production right is central to seed quality. All-male fish are produced by feeding hormone-treated feed containing 17-alpha-methyltestosterone to fry no more than about 17 days old, for 21 to 28 days.13 If it is done badly, the fish breed in the cage instead of growing. It is also a skill an entrant can sell before they ever run a grow-out cage.
An empty cage earns nothing| Decision | The benchmark | What it means for the entrant |
|---|---|---|
| Fingerling size at stocking | above about 10 grams | Bigger seed survives better; cheap tiny fry often cost more in losses |
| Sex | all-male (monosex) | Males grow faster and more evenly; mixed batches breed and stunt |
| Stocking density (cage) | about 50 to 80 fish per cubic metre | Crowding raises disease and drops survival |
| Strain | Akosombo, the only approved improved strain | Buy approved, screened Akosombo seed |
| Health status | screened, from a known source | The most important check against a disease outbreak |
| Time to table size | about five to six months to 350 grams | Sets how many cycles a year are possible |
Catfish has several advantages over tilapia. In European tank systems, African catfish yields about 300 kilograms (Hungarian flow-through tanks) to 1,500 kilograms (Dutch recirculating systems) of table fish a cubic metre a year at a feed conversion of about 0.9 to 1.4, reaching about 1.1 to 1.6 kilograms in 30 to 50 weeks from hatching.14 It tolerates the crowding and poor water that would trigger a tilapia die-off, which makes it the lower-risk entry for a first-time farmer with an imperfect site.
Oxygen makes a big difference. In a 12-week trial in treated-wastewater ponds in Kumasi, catfish stocked at about 39 grams reached about 189 grams in aerated ponds against about 91 grams in unaerated ponds, and the aerated ponds made a small profit where the unaerated ones made a loss.15 Because most catfish is sold live or smoked, it also avoids the cold-chain problem that hurts fresh tilapia (see Pillar 6).
Sold live or smokedWhat this means. Catfish spreads the risk within the sector. It is harder to kill, cheaper to start and sold for cash in a live market. It also copes with the poor water and small budgets that cause many first-time tilapia farmers to fail. For a student or an entrant with little capital, catfish is often the better first cage. Tilapia can follow once the skills and the site are tested.
A certified tilapia hatchery. Each clean, screened fingerling produced in Ghana helps fill the supply gap and slows the spread of disease. This is the strongest opening in seed, and the national plan is trying to fund it.
A catfish hatchery and fingerling nursery. Catfish seed is a separate, under-served supply, and the live-fish trade downstream is steady and cash-based.
A fingerling nursing and grading service, which takes small fry through the fragile early weeks and sells stronger, screened, size-graded fingerlings to grow-out farmers who cannot risk weak seed.
The seed itself is the main way disease moves between farms. Because many farms buy fingerlings from other farms, a batch of seed can carry a virus onto a clean site before a single fish shows a symptom.
About half of infected fish show no symptoms, and about 63 percent of 30 Lake Volta farms surveyed had sourced seed from a virus-positive farm.6
Every grow-out farmer, but hardest on newcomers who buy the cheapest seed from whoever has stock.
Buy only screened seed from a hatchery that will state its health status, and stock a small test batch first. The matching opening is a certified-seed or fingerling-screening service, since buyers need seed they can trust.
There are not enough fingerlings, so a farmer may not get the quantity, size or strain they planned for, when they need it. A cage left empty waiting for seed is capital earning nothing.
Hatchery output fell from about 615 million fingerlings in 2022 to about 382 million in 2024, below the Ministry’s 544 million target,108 and seed availability is a main cause of stagnating tilapia output.9
Small and new farmers without a standing hatchery relationship, who are served last.
Book seed ahead on a written schedule, and treat a reliable hatchery relationship as more valuable than a cheap one-off batch. The opening is local hatching, which turns the shortage into a business.
Picking a strain on growth speed alone, and ignoring how it copes with heat and low oxygen, can produce a fast-growing cage that dies in a hot, still week before it reaches harvest.
The Akosombo strain has a median lethal temperature of about 45.1 degrees Celsius against 41.5 for GIFT, and survival to harvest was about the same for both.45
Farmers on shallow, warm or crowded sites who buy the fastest strain by reputation.
Stock approved Akosombo seed, which copes better with low oxygen, and manage stocking density and aeration on warm, still sites. The opening is strain-selection advice and site-matched seed supply.
Screened seed firstWhere this connects. Seed quality affects survival, which is covered under disease in Pillar 3. Stocking density feeds into the production systems in Pillar 4 and the cost model in Pillar 5. The hatchery opening returns as an entry point in Pillars 6 and 8, and the border rules on improved strains link to the fish import rules in Pillar 2.
Tilapia and catfish are two separate businesses. Tilapia is a fresh-fish, cage, volume trade; catfish is a hardy, live-or-smoked, lower-risk niche. Choose by the market you can reach.
Akosombo is the only approved improved strain; GIFT grows faster in trials but is not approved, and survival to harvest was about the same for both. Buy screened Akosombo seed.
The fingerling is the main bottleneck. Hatchery output fell to about 382 million in 2024, below target, and infected seed spreads disease between farms.
That shortage is the clearest opening. A certified hatchery or fingerling-nursing service fills the gap and slows disease at the same time.
Catfish spreads the risk. It is harder to kill, cheaper to start and sold for cash, and it is often the better first cage.