Ask most people where fish comes from and they'll say "the market." Ask a tilapia farmer, and you'll get a much longer, much more interesting answer — one that starts months earlier, in a hatchery, with fish barely the size of an eyelash.
Here's what actually happens between a tilapia's hatching and its arrival at harvest weight.
Healthy adult tilapia — the broodstock — are kept in dedicated breeding ponds, selected for growth rate and body condition. Tilapia are mouth-brooders: after spawning, the female holds fertilised eggs in her mouth, protecting them until they hatch into free-swimming fry.
Newly hatched fry are fed a specially treated starter feed for a short window, which reverses their sexual development so the population grows out as all-male. This matters more than it sounds: mixed-sex ponds breed uncontrollably, crowding themselves out and stunting growth. All-male ponds grow faster, more evenly, and stay at a predictable, manageable number.
From there, fry move into nursery ponds or tanks, fed a fine, protein-rich diet and shielded from predators and poor water quality. Over several weeks they grow from roughly a gram into fingerlings — sturdy enough to be graded, counted, and stocked out into grow-out ponds.
This is the longest stretch of the journey — typically a few months — where fingerlings put on the bulk of their weight. Stocking density, feed schedule, and water quality management all happen here, and feed conversion ratio (how much feed it takes to produce a kilo of fish) becomes the number every serious farmer tracks closely, since it drives both cost and profit.
Once fish reach market weight, ponds are netted and fish are graded by size — larger fish sold immediately, smaller ones returned to keep growing, letting a single pond support multiple harvest rounds.
It's a longer road than most people imagine — but understanding each stage is exactly what separates a farm that survives from one that thrives. See the full training programme →
