29 April 2021by administrator

SFR | FCR | SGR | GF3 | FCE | BWG | RGR | PER | FI:FO | ADG | B-FCR | E-FCR | K
Summary of parameters and terms used in aquaculture

FCR: Feed Conversion Rate

FCR represents kilograms of feed needed to produce one kilogram of fish.

  • FCR= Feed given / Animal weight gain

SGR: Specific Growth Rate

SFR is a coefficient that measures the percentage increase in fish weight per day.

  • W0[g]= the weight in grams at the beginning of the period
  • Wt [g]= the weight in grams at the end of the period
  • t[d]= period, expressed in number of days
  • Ln = natural logarithm

SFR: Specific Feeding Rate

SFR corresponds to the amount of food eaten per day and expressed as a percentage of the fish’s body weight.

GF3: Thermal Growth Coefficient

Measure of daily growth in a given period that takes into account temperature.
GF3 = [(W2(1/3) – W1(1/3) ) / ºD ] x 1000

  • W2 = weight (g) at time 2 (end of period)
  • W1 = weight (g) at time 1 (beginning of period)
  • ºD = Degree-days, sum of daily temperatures in °C between t1 and t2 (or duration in days x average temperature in period)

FCE: Feed Conversion Efficiency

The efficiency of a feed is normally measured by the amount necessary to produce a unit weight of fish.
FCE= Wt of food presented / Wt of animal produced

  • Wt = means the weight in a certain period

BWG: Body Weight Gain - PG: Peso Ganado

PG (g) = Final weight – initial weight

RGR: Relative Growth Rate

RGR (%) = Final weight – initial weight / initial weight

PER: Protein Efficiency Ratio

PER (%) = Increase in biomass in the tank / total protein ingested

FI:FO: Fish In Fish Out

Amount of wild fish needed to produce 1 kg of aquaculture fish
FI:FO (%) = FCR x (% fish meal + % fish oil in feed)

ADG: Average Daily Gain

Growth rate
Average daily gain (g) = body weight gain (g) / number of days

Survival Rate

Survival rate % = number of surviving animals at the end of the production cycle / total number of animals at the beginning of the cycle * 100

B-FCR: Biological Feed Conversion Rate

Takes into account feed used, and all Biomass generated, including lost Biomass.
E-FCR = Amount of feed (kg) / (Biomass2 – Biomass1)

  • Biomass1= Biomass at the beginning of the period
  • Biomass2 = Biomass at the end of the period
  • Lost Biomass= Biomass lost during the period (mortality, elimination)

Stocking Density

Total fish Biomass per unit of tank volume
D = W / V

  • D = Stocking density (kg/m3)
  • W = Biomass (kg)
  • V = volume (m3)

Fork Length

Fork length (also referred to as length or standard length) is the length (cm) of a fish from the tip of its nose to the middle of the tail fork.

K: Condition factor

Fork length (also referred to as length or standard length) is the length (cm) of a fish from the tip of its nose to the middle of the tail fork.

Condition factor (K) is an indicator of the leanness/fattiness of a fish, which is generally regarded as an indicator of fish´s health. If K is less than 1, fish are considered thin or poorly nourished, for higher than 1 levels, the relation of K to fattiness is usually species dependent.

K = [(W x 100) / L3]

  • K = Condition factor
  • W = weight (g)
  • L = length (cm)
Would you like to contribute to the post about the terms used in aquaculture sector, either by correcting any erroneous information or providing any other term that is not included? Send an email to fishfarmfeeder@fishfarmfeeder.com

If you plan to upgrade your farm or build a new one, do not hesitate to contact us. We provide tailor-made feeding systems for land-based, RAS, river and/or lake aquaculture for more than a decade.


Founded in 2008, we manufacture only feeding systems for Aquaculture, feeding all stages of the life of the fish and/or shrimp.


Do you want to keep up to date with the latest news?
Subscribe to our newsletter

Copyright 2024 © FishFarmFeeder

Privacy Policy | Legal Notice | Cookies Policy

Copyright 2024 © FishFarmFeeder. Todos los Derechos Reservados