How do I estimate fish growth rate?

Growth rate is typically measured as average daily gain (ADG) in grams per day. Weigh a sample of fish at two time points, calculate the average weight difference, and divide by the number of days between samples.

What is a typical growth rate for tilapia?

Tilapia typically grow 2–5 g/day under optimal conditions (28°C, good water quality, adequate feeding). Growth varies with strain, diet, and environment.

What market size should I target?

Market size depends on your buyer. Whole tilapia typically sell at 400–600g. Salmon for fillets are usually harvested at 3–5 kg. Check local market requirements.

Can I export the harvest date to my calendar?

Yes — click the "Export to Calendar" button to download an .ics file that can be imported into Google Calendar, Outlook, or Apple Calendar.

ToolsConductScience tool

AquacultureFree in-browser calculator

Harvest Timing Planner.

Project your harvest date based on current weight and growth rate. Export to calendar with one click.

Run calculator Request a Quote

PrivateData stays in your browser

LiveNo sign-up required

Validated2026-04-08

CitableMethods and citation included

Calculator

Results update in place

Try it out

Load example harvest planner data to see the full workflow

Growth Parameters

Current Weight (g)

Target Weight (g)

Growth Rate (g/day)

Results

60days to harvest

Estimated harvest date: 8/17/2026

Days to Harvest

estimated

Harvest Date

8/17/2026

projected

Growth Rate

5 g/d

daily gain

When to use

Planning harvest logistics (labor, equipment, transport)
Coordinating with buyers on delivery schedules
Projecting production timelines for new cohorts
Adjusting feeding strategy to hit market windows

Do not use for

Without regular sampling — update growth rate estimates monthly
When fish health problems are affecting growth — actual rates may be lower than projected

Growth is not perfectly linear

Fish growth follows an S-curve. Early and late stages are slower. This tool uses a linear approximation, so adjust expectations for extreme growth phases.

Temperature affects growth rate

Seasonal temperature changes can dramatically alter growth rate. Re-estimate ADG after major temperature shifts.

Feed restriction delays harvest

If feed is limited (by budget or supply), actual growth will be slower than potential. Plan feed inventory to match growth targets.

Method

Linear growth projection: Days to Harvest = (Target Weight – Current Weight) / Growth Rate. Calendar export uses RFC 5545 iCalendar format.

Validated

Last validated 2026-04-08. Calculations are designed for planning and documentation support; verify procurement decisions against manufacturer specifications or institutional SOPs.

How to cite

How to Cite

ConductScience Harvest Timing Planner (v1.0). ConductScience, Inc. 2026. Available at: https://conductscience.com/tools/harvest-timing-planner

Rakocy JE. Aquaculture Engineering: Tilapia Culture in the Americas. World Aquaculture Society. 2010.

Harvest Timing in Aquaculture

Timing the harvest correctly is critical for profitability. Harvesting too early means selling undersized fish at lower prices, while harvesting too late wastes feed on fish that have passed their most efficient growth phase. This tool projects the harvest date based on linear growth rate, helping operators plan labor, logistics, and market timing. Export the projected date to your calendar for automated reminders.

Frequently asked

325

Free tools

1,200+

Institutions

100%

Client-side

Uploads required

Next steps

Equipment