For tilapia grown in earthen ponds, PC Farm Thailand's grower's handbook recommends 3–5 fish per m² without mandatory aeration, or 8–15 fish per m² with paddlewheel aeration. In a full-feed pond at about 10 fish per m², our fish grew from 0.65 g to 1,000 g in 4.5 months with a feed conversion ratio of 1.2. This guide covers pond preparation, density by stage, feeding rates, water quality and survival planning.
· PC Farm Thailand (Farm Story Co., Ltd.) · Chachoengsao, Thailand
At a glance
| System | Earthen grow-out pond — the most common way to farm tilapia in Thailand |
|---|---|
| Density, semi-intensive | 3–5 fish per m² · aeration optional (use in the hot season) · easy to manage |
| Density, high | 8–15 fish per m² · paddlewheel aeration required · exchange 10–20% of the water per week |
| Water depth | 1.2–1.5 m for grow-out |
| Feed | Pellet feed, 40% protein for 1–5 g fish stepping down to 25–28% at 400–600 g |
| Time to market size | About 3 months to 500–600 g under full feeding (handbook value) |
| Recorded result | 0.65 g to 1,000 g in 4.5 months at about 10 fish/m², ADG 8 g/day, FCR 1.2, mortality under 15% — growth data |
| Fry & fingerlings | Sex-reversed (all-male) Giant Black and Giant Red from PC Farm Thailand |
Figures marked as handbook values are reference ranges from PC Farm's grower's handbook for Giant Black & Red tilapia under good conditions in Thailand. They are planning targets, not guarantees — adjust to your own sampling and water readings.
Ask about fry for your pondGetting started
Good preparation gives the fry natural food and stable water from day one.
Dry the pond out, then apply lime at 60–100 kg per rai (1 rai = 1,600 m²).
Fill to 1–1.2 m and leave 5–7 days for natural food to bloom before stocking.
Stock in the early morning or evening. Float the transport bag in pond water for 15–20 minutes first so the fry adjust to the temperature.
Scatter a little feed at a time until the fish slow down, then stop. Never let feed settle uneaten.
Weigh 30 fish, take the average and recalculate the feed amount. Grade big and small fish apart to reduce feed competition.
Density
Higher density demands more oxygen, water exchange and management. Without aeration, use the lower end of each range. Separate ponds per stage are recommended.
| Stage | Fish weight | Density (earthen pond) | Duration | Notes |
|---|---|---|---|---|
| Nursery | 1–30 g | 50–100 fish/m² | 4–6 weeks | Small pond, easy control; thin out gradually |
| Small grow-out | 30–150 g | 8–15 fish/m² | 6–8 weeks | First grading |
| Large grow-out | 150–600 g | 3–8 fish/m² | 8–12 weeks | Aeration needed above 5 fish/m² |
Handbook values for earthen ponds.
Feeding
Smaller fish eat a larger share of their body weight and need higher protein. Recalculate the amount every time you sample-weigh.
| Fish weight | Feed per day (% of body weight) | Protein | Meals per day | Pellet size |
|---|---|---|---|---|
| 1–5 g | 8–10% | 40% | 4–5 | Powder–0.8 mm |
| 5–20 g | 6–8% | 35% | 4 | 1–2 mm |
| 20–50 g | 5–6% | 32% | 3–4 | 2 mm |
| 50–100 g | 4–5% | 30% | 3 | 2–3 mm |
| 100–200 g | 3–4% | 30% | 2–3 | 3 mm |
| 200–400 g | 2.5–3% | 28% | 2 | 4 mm |
| 400–600 g | 1.5–2.5% | 25–28% | 2 | 4–5 mm |
Handbook values. Cut back or skip feeding when oxygen is low at dawn, the weather shifts, it rains heavily or fish look sick.
Water quality
Nearly all fish disease starts with the water. Keep these parameters in range, then follow the routine consistently.
| Parameter | Target | Notes |
|---|---|---|
| Water temperature | 28–32 °C | Best growth; tolerable 24–34 °C |
| Dissolved oxygen (DO) | Above 4 mg/L | Above 5 is ideal; critical below 3 |
| pH | 6.5–8.5 | Optimal 7–8 |
| Ammonia (NH₃) | Below 0.05 mg/L | Lower is better |
| Nitrite (NO₂) | Below 0.5 mg/L | |
| Transparency | 30–40 cm | Secchi disk; light green water |
| Water depth | 1.2–1.5 m | Earthen grow-out pond |
| Hardness | Above 50 mg/L as CaCO₃ | Supplement with lime |
Handbook targets. Danger signs to act on at once: fish gulping air at the surface at dawn, sluggish swimming or not eating, blotchy skin, sores or eroded fins, or several deaths in a row. Turn on the paddlewheel, stop feeding, change part of the water and isolate sick fish.
Routine
Feed each meal and watch the feeding response. Walk the pond at dawn and run the paddlewheel if fish are surfacing. Remove dead fish and leftover feed; log mortality.
Measure pH and transparency. Exchange 10–20% of the water in dense ponds. Add probiotics to help break down bottom waste.
Sample-weigh 30 fish and recalculate the feed amount. Grade the fish to reduce competition.
Check gills, skin, fins and external parasites. Apply lime at 20–30 kg per rai if pH needs adjusting. Reassess survival and reduce density if overcrowded.
Survival
Risk is highest in the nursery stage, when fish are small and adjusting to a new pond. Harvest count = number stocked × cumulative survival.
| Stage | Fish weight | Survival | Loss | Main causes of loss |
|---|---|---|---|---|
| Nursery | 1–30 g | 80–90% | 10–20% | Handling stress, water quality, predators |
| Small grow-out | 30–150 g | 90–95% | 5–10% | Disease (Trichodina, bacteria), low oxygen |
| Large grow-out | 150–600 g | 92–97% | 3–8% | Water fouling from waste, sudden weather change |
| Whole cycle | 1 → 600 g | 75–85% | 15–25% | Cumulative across all stages |
Handbook planning ranges for earthen ponds. In our recorded growth result, mortality was less than 15% — see the growth data.
Choosing a system
Reference densities for grow-out to about 500–600 g.
| Culture system | Density | Aeration | Water exchange | Management |
|---|---|---|---|---|
| Earthen pond — semi-intensive | 3–5 fish/m² | Optional / hot season | As water dictates | Easy |
| Earthen pond — high density | 8–15 fish/m² | Paddlewheel required | 10–20% per week | Moderate |
| Cage in flowing water | 50–80 fish/m³ | Relies on water flow | Natural | Moderate |
| Tarpaulin pond / RAS | 20–40 fish/m² | Continuous (required) | Filtration / recirculation | Intensive |
Handbook values. PC Farm supplies fry and fingerlings for all three systems and field-tests its breeding lines in earthen ponds and cages.
Good to know
PC Farm's grower's handbook recommends 3–5 fish per m² for semi-intensive ponds, where aeration is optional, and 8–15 fish per m² for high-density ponds, where paddlewheel aeration is required. Our recorded growth result comes from a 1,600 m² pond stocked with 16,000 fry, about 10 fish per m².
As a handbook reference, about 3 months to reach 500–600 g under full feeding. In our recorded earthen-pond result, fish stocked at 0.65 g averaged 500 g at month 3, reached 1,000 g in 4.5 months and 1,200 g at month 5. Cool weather below 25 °C can extend the cycle by 3–6 weeks.
Feed as a percentage of total body weight per day: 8–10% for 1–5 g fish, falling step by step to 1.5–2.5% for 400–600 g fish. Recalculate after every sample weighing, feed by observation and never leave feed uneaten.
Smaller fish need more protein: 40% for 1–5 g fish, 35% for 5–20 g, 30–32% for 20–200 g, 28% for 200–400 g and 25–28% for 400–600 g. Our recorded growth result used feed with 30–32% crude protein.
The handbook planning range for a whole cycle from 1 g to 600 g is 75–85%, with most losses in the nursery stage. In our recorded growth result, mortality was less than 15% with dissolved oxygen kept at 5–9 mg/L.
Keep an earthen grow-out pond at 1.2–1.5 m. When preparing a new cycle, fill to 1–1.2 m and wait 5–7 days before stocking.
Yes. PC Farm Thailand supplies sex-reversed, all-male Giant Black and Giant Red fry and fingerlings to pond farms across Thailand and to export customers. Tell us your pond size and target harvest weight and we will advise on stocking.
Tell us your pond size, aeration and target harvest weight — we'll advise on stocking and confirm availability and a quote in THB or USD.