Greenfield tilapia RAS: a sized, costed RAS + MBBR design in one pass (illustrative)
A greenfield 55 t/yr indoor tilapia brief — 550 m³, 110 kg/day feed, grid power, municipal discharge — went in; a route recommendation, unit sizing, a costed bill of materials and internal consistency checks came out. AquaMind V2 selected RAS + MBBR, sized the biofilter, aeration, pump and tankage from the computed nitrogen and oxygen loads, and self-verified that every sized unit maps to a BOM line. Illustrative sample on a fictional facility.
Summary
From a 550 m³ system producing 55 t/yr on 110 kg/day of feed, AquaMind V2 computed a TAN load near 4.05 kg/day and an oxygen demand near 46 kg/day, then recommended a recirculating RAS + MBBR route and sized each core unit against those loads. The design passed three internal consistency checks — biofilter sizing recompute, BOM internal arithmetic, and BOM completeness — before delivery.
Findings
Route: RAS + MBBR
Tilapia tolerate intensive recirculation, and the brief's feed-loading intensity — ~4.05 kg/day TAN, ~46 kg/day O2 demand in 550 m³ — is far beyond what flow-through or pond/biofloc-only systems could assimilate without enormous water exchange. A greenfield indoor site on grid power with municipal discharge favours RAS: minimal water use, tight water-quality control, and waste concentrated into a manageable sludge stream for simpler discharge compliance.
Unit sizing from first-principles loads
Biofilter media ~13.5 m³ (8,096 m² media area against the 4,048 g/day TAN load), aeration blower ~0.68 kW (45 m³/h air for ~46 kg/day O2 demand), process pump ~18.9 kW against an 8.2 m total dynamic head, and 550 m³ of tankage.
Self-verified consistency
Three checks passed: the biofilter sizing recompute matched, the BOM total equals the sum of subtotals with each line equal to quantity × unit cost, and every sized unit has a corresponding BOM line — no orphan equipment, no unpriced units.
Treatment plan
- 01
Bill of materials — indicative capex ≈ US$221k
Tankage US$192,500 (550 m³), pump US$17,021 (18.9 kW), biofilter media US$10,795 (13.5 m³) and blower/aerator US$811 (0.68 kW). Figures are indicative equipment capex for route comparison, not a final quotation.
- 02
Next step — validate assumptions before build
Confirm stocking density, feed formulation and local energy/discharge constraints, then firm the sizing margins. The design is delivered as an engineering starting point for a detailed-design phase, not an execution-ready spec.