Grow-out walkthrough 01
Whiteleg shrimp grow-out — from stocking plan to comparable bids
A coastal site is planned for intensive vannamei grow-out. Aerator quotes arrive before anyone has agreed an oxygen demand, so every offer answers a different question.
Planning basis
- System
- Lined intensive ponds or indoor raceways
- Planning inputs
- Pond area, stocking density (PL/m²), target harvest weight, cycles per year
- Benchmarks used
- FCR 1.3–1.6, survival 60–85%, 2–3 cycles/year in warm climates
- Critical constraint
- Dissolved oxygen at peak biomass, and power reliability
How the project is worked
1 · Production plan before equipment
Stocked post-larvae, expected survival, harvest weight and cycles per year give standing biomass. Peak biomass — not average — sets aeration, pumping and feeding duty.
2 · Oxygen demand calculated, not guessed
Oxygen demand is derived from biomass, water temperature and daily feed, then converted into kg O₂/h and kWh per kg O₂ so aerators are compared on delivered oxygen rather than horsepower.
3 · Water and biosecurity scope written in
Intake filtration, reservoir, settling, disinfection and effluent handling are stated in the RFQ so they are priced by every supplier instead of appearing later as a variation.
4 · Nursery decision taken early
A nursery stage changes pond turnover, PL logistics and equipment scope, so it is fixed before quotes, not after.
5 · One RFQ text, normalised bids
Aeration, pumping, feeding, monitoring, harvest and installation go out as one scope with one incoterm; returned offers are re-tabulated line by line.
What the RFQ must price
- Aeration: kg O₂/h delivered at site salinity and temperature, plus kWh per kg O₂
- Pumping: flow, head, redundancy and standby units
- Water treatment: intake screening, reservoir, disinfection, effluent
- Feeding: automatic feeders or blowers, hoppers, control
- Monitoring: DO, temperature, salinity, pH sensors and alarms
- Backup power: generator sizing and emergency aeration
- Installation, commissioning and operator training days
Where these projects go wrong
- Pricing aerators by horsepower instead of delivered oxygen.
- Sizing on average biomass instead of the final weeks of the cycle.
- Leaving effluent and intake treatment out of the scope until permitting raises it.
- No emergency aeration or generator, on a site with unstable grid power.
Run these before briefing suppliers
These are illustrative grow-out walkthroughs, not client case results. They show how a project of this type is sized and taken to a human-reviewed RFQ. No client or supplier is identified, no prices are published, and no yield, cost or delivery outcome is claimed. Biological and cost assumptions require validation by a qualified specialist.