Pond Design, Stocking Density & FCR Guide
Start with working water volume and batch biomass. Then check feeding, aeration, drainage and equipment scope before requesting a quotation.
Preliminary guidance, not an approved design. Species, life stage, soil, climate and water quality require qualified local validation. No universal stocking densities, market prices or guaranteed outcomes are provided.
Pond design options
Visitor-entered concept brief. Shape, banks and working water level come first; inlet and outlet arrangements need site-specific hydraulic, soil and biosecurity review.
Waterline to bed; exclude dry freeboard. A varying bed needs surveyed mean depth.
0 means vertical walls, not a recommended earth-bank slope. Soil, liner and stability checks determine a suitable slope.
Site review checklist
- Measure length and width at the working waterline. The sloped-bank volume formula requires straight, equal banks and a flat bed.
- Confirm available gravity head through seasonal water levels, screen losses and intake protection.
- Verify bed fall toward the drain, isolation, sediment access and permitted discharge.
- Separate intake and discharge to limit short-circuiting and contamination. Check flood levels, freeboard, overflow, erosion protection and local permits independently.
Enter a positive water depth and a non-negative slope to download the brief.
Planning only: no safe stocking density, pump size, drain diameter or bank stability is inferred. Review with a qualified local engineer. Choices stay on this page and are not sent to the CRM.
Pond layout & equipment recommendations
Concept layouts for a site discussion—not construction drawings or equipment sizing approval. Keep intake, production, discharge and service access distinct. Surveys and the production plan determine actual positions.
Specify packages before asking for offers
Screened intake, valves & pump
Use pumping only when gravity cannot meet the duty. Specify flow at total dynamic head, seasonal water levels, screen losses, materials and isolation.
Aeration & circulation
Compare paddlewheels, aspirators or diffused air against oxygen and circulation needs. Request transfer-test evidence and field corrections; assess peak demand, dead zones, sediment movement and redundancy.
Drain, level control & solids collection
Select a standpipe, monk or low-point drain for the surveyed bed and harvest method. Check full drainage, screens, clogging, erosion, sediment access and permitted discharge.
Water-quality monitoring & alarms
Plan dissolved-oxygen and temperature monitoring; other measurements depend on species and water chemistry. Specify calibration, sampling locations, alarm response and power/network failure arrangements.
Electrical distribution & backup
Review backup for critical aeration, pumps and alarms. A qualified electrician should verify wet-site protection, starting loads, transfer arrangements and maintenance access.
Liner, feeding & harvest equipment
A liner depends on soil and water-retention needs. Review subgrade, seam tests and repairs; select feeders and harvest gear from the production plan, not pond area alone.
No manufacturer, price, capacity or guaranteed outcome is recommended. Collect dated, comparable quotes after qualified local review. General references: FAO, Simple methods for aquaculture: pond construction (site layout, supply and drainage); SRAC 3700, Pond Aeration. Neither provides site approval.
1. Pond shape and working water volume
Measure average working water depth, not maximum excavation depth. Length × width × average depth applies to a rectangular pond with vertical sides. For sloped banks, irregular beds or islands, use surveyed site cross-sections. Dry freeboard above the water does not count as usable volume.
V (m³) = L (m) × W (m) × average depth (m); 1 m³ = 1,000 L
2. Bank slopes, inlet and outlet
Choose the shape around topography, access and circulation. A qualified practitioner must check bank and soil stability. Separate intake and discharge to limit unintended recirculation; define level control, drainage, solids collection and harvest access. Concept drawings do not specify construction dimensions.
3. Stocking density and biomass: state the unit
Density in kg/m³ is biomass divided by working water volume; animals/m² and animals/m³ are different measurements. If starting from animal numbers, estimate final biomass using your entered survival and individual final weight. Do not apply survival again to a final biomass that already includes it. Allowable density depends on species, life stage, water, feeding and oxygenation capacity.
D (kg/m³) = biomass (kg) ÷ V (m³); final biomass = initial animal count × survival (fraction) × final individual weight (kg)
4. Aeration and supporting equipment
Size from peak oxygen demand and actual transfer under pond conditions, not rated motor power alone. Check peak feeding, temperature, salinity and night-time measurements. Review intake and pumps, aerators, drains, oxygen sensors, alarms, backup power, liners and feeding/harvest equipment without favoring brands.
5. FCR and feed cost
Use feed actually supplied and reconciled biomass gain for the same batch and period. Record partial harvests, transfers and mortality; state whether you calculate biological or economic FCR. Multiplying FCR by delivered feed price estimates only feed cost per kg of gain, not total cost or margin.
FCR = feed supplied (kg) ÷ biomass gain (kg); feed cost/kg of gain = FCR × feed price/kg
6. Prepare a comparable project request
Document species, volume, peak biomass and feeding, water, electricity, backup and timeline. Separate civil works, liners, equipment, transport, installation, testing and operating costs. Use your own dated prices with currency and inclusions; unknown amounts stay unpriced. Request the same scope and acceptance criteria for each offer.
Pond design questions
Does pond volume determine a safe stocking density?
No. Volume is one input; species, life stage, peak feed, oxygen transfer, water quality and backup capacity require site-specific review.
Should survival be applied twice to final biomass?
No. When final biomass already includes survival, do not multiply it by survival again. From animal counts, use initial count × survival fraction × final individual weight.
Does FCR multiplied by feed price give total production cost?
No. It estimates feed cost per kg of biomass gain only. Seed, electricity, labor, maintenance and other costs require separate dated inputs.
Related calculators and guidance
Sources and limits: FAO, pond construction manual; SRAC 3700, Pond Aeration; Mississippi State University, Feed Conversion Ratio for Pond-Raised Catfish. These are technical references, not current prices or approval for your site.