Stocking densities used
| Species & system | Density | Fingerling size |
|---|---|---|
| African catfish, tank without aeration | 100–200 /m³ | 5–7 cm |
| African catfish, biofloc + strong aeration | 300–500 /m³ | 5–7 cm |
| African catfish, earthen pond | 50–100 /m² | 5–7 cm |
| Tilapia, earthen pond without aeration | 3–5 /m² | 5–8 cm |
| Tilapia, tank + aeration | 20–50 /m³ | 5–8 cm |
| Pangasius, earthen pond | 10–20 /m² | 2–3 inches |
| Giant gourami, earthen pond (grow-out) | 5–10 /m² | ≈ 50 g |
General values from tropical pond practice, deliberately moderate. Many online claims are far higher (e.g. 1,000 catfish/m³ in biofloc), but those need experience, strong aeration and power that never fails.
Round tanks quick table
Round tarpaulin and steel-frame tanks are popular for catfish. With 0.8 m of water:
| Diameter | Volume | Catfish, no aeration | Catfish, biofloc |
|---|---|---|---|
| 1 m | ≈ 628 L | 63–126 | 188–314 |
| 2 m | ≈ 2,513 L | 251–503 | 754–1,257 |
| 3 m | ≈ 5,655 L | 565–1,131 | 1,696–2,827 |
| 4 m | ≈ 10,053 L | 1,005–2,011 | 3,016–5,027 |
Why start at the low end
- Oxygen runs out faster in crowded tanks, especially before dawn.
- Ammonia from waste and feed builds up faster (check with the ammonia calculator).
- Disease spreads faster among crowded, stressed fish.
- Uneven growth: bigger fish win the feed, and catfish can turn cannibalistic.
A slightly looser pond that stays healthy usually earns more than a crowded one with heavy losses.
Stocking tips
- Acclimate: float the bag 15–30 minutes to match temperature, then mix in pond water little by little.
- Stock in the morning or evening, not in the midday heat.
- Don't feed for a few hours after stocking, then start small.
- Grade by size regularly, especially catfish, to reduce cannibalism.