Fish Farming Economics: Building a Cost Per Kilogram Model

Aquaculture projects are rarely killed by capital cost. They are killed by a production cost per kilogram that lands above the farmgate price the market pays. The discipline is to build cost per kilogram bottom-up, then stress it — before any equipment is ordered. Work alongside the operating cost calculator and the commercial ROI calculator.

The cost stack

For most commercial finfish operations, production cost per kilogram breaks down roughly as: feed 40–60%, juveniles 8–15%, energy 8–20% (highest in RAS), labour 8–15%, health, consumables and maintenance 5–10%, and depreciation plus financing 10–20%. Proportions move by system and geography, but feed ranking first is near-universal.

Feed: the ratio that dominates everything

Economic FCR — feed used divided by fish actually sold — is not biological FCR. Mortality, feed waste, grading losses and escapes all inflate it. A farm modelled at 1.3 that operates at 1.6 has added roughly 20% to its largest cost line. Model it honestly with the FCR calculator and the feed budget calculator.

Mortality compounds

Survival does not reduce revenue proportionally — it multiplies cost. Fish that die at 60% of harvest weight have already consumed 60% of their feed, their juvenile cost, their oxygen and their labour, and return nothing. Moving survival from 92% to 85% typically raises cost per kilogram by 6–10%, which is often the entire margin.

Energy is a system choice

Pond and cage systems may spend €0.10–0.30 per kilogram on energy; commercial RAS commonly spends €0.50–1.20 depending on tariff and climate. That gap is the real economic difference between systems, and it is why a RAS at a €0.25/kWh tariff and a RAS at €0.08/kWh are different businesses. Test it with the energy cost calculator.

Labour scales in steps, not smoothly

A farm needs a minimum competent crew regardless of volume: shift coverage, a technical manager, a biologist. That fixed block is why sub-scale projects rarely work — below roughly 100–200 tonnes per year for RAS, labour per kilogram becomes punishing. Scale is the cheapest cost reduction available to most projects.

Working capital and the ramp

The first cycle produces cost without revenue. Juveniles, feed, energy and salaries run for the full grow-out period before the first harvest, and a RAS typically reaches steady state 9–15 months after commissioning. Projects that finance CAPEX but not the ramp run out of cash while biologically succeeding — the most avoidable failure in the sector.

Price is an assumption, not a fact

Use conservative farmgate prices net of harvest, processing, logistics and commission — not retail prices, and not the peak of a strong year. If the project only works at the top of the historical price band, it does not work.

Stress the model before the lender does

Run at least three scenarios: base, pessimistic (FCR +15%, survival −7 points, energy +30%, price −15%) and optimistic. Lenders will run the pessimistic case regardless; showing you have already done it is what makes a project bankable. See what lenders require and the financing pathway guidance.

Then price the CAPEX against the model

Only once cost per kilogram stands up does capital cost matter — because now you can judge whether an extra €300k of automation or heat recovery earns its return. Use the CAPEX estimator, the RAS cost breakdown and the aquaculture CAPEX guide.

FishMatch Group is an independent aquaculture project sourcing and RFQ platform. We are not a fish farm, feed producer, equipment manufacturer, EPC contractor, lender, broker-dealer, investment advisor or financial advisor. Supplier and project partner outreach happens only after a commercial project brief is reviewed. Start with a human-reviewed RFQ.