The 3 Basic and Conceptual Errors That Increase FCR in Marine Fish

By: Victor Vargas

The Feed Conversion Ratio (FCR) is one of the most decisive indicators of profitability in marine fish farming. Even a small deviation in feeding efficiency can turn a profitable cycle into a deficit. Yet in many farms, three conceptual errors continue to raise FCR without contributing any real improvement in growth.

The first error occurs when feeding strategies are applied without validating the actual growth curve of the stock. It is still common for feeding decisions to rely on theoretical tables or historical references that no longer reflect the current condition of the fish or the environmental dynamics of the cycle. When real growth drifts away from the expected trajectory and feed rations are not adjusted in time, an oversupply of feed inevitably appears. This surplus does not translate into biomass; it directly increases FCR and creates the illusion that the problem lies in the feed itself, when the real issue is the lack of validation and timely adjustment.

The second error emerges when farms fail to identify the inflection point of the growth curve. This moment marks the beginning of a phase in which the growth rate starts to slow down and the fish can no longer convert feed with the same metabolic efficiency. Although the fish continue to grow, they do so at a higher energetic cost: more feed is required to achieve the same weight gain. If this physiological shift goes unnoticed—whether due to inadequate monitoring, temperature variations, stocking density, or simply the absence of clear technical criteria—the feeding strategy continues supplying a high ration at a stage where each gram of feed produces diminishing returns. As a consequence, the production cycle becomes unnecessarily longer, feed costs increase, and FCR deteriorates without generating meaningful benefits. In simple terms: feeding past the inflection point means investing more to gain less.

The third error arises when feeding is treated as an operational task rather than a strategic process grounded in reliable information. Many farms still lack standardized protocols to record feed consumption, evaluate feeding behavior, or analyze thermal and metabolic changes. This absence of structure produces constant “data noise”: inconsistent information that distorts key indicators such as growth, feed intake, and efficiency. When data is imprecise or non-comparable, decision-making becomes reactive and subjective, and system efficiency quietly erodes over time.

These three errors share a common root: data quality. In aquaculture, the greatest challenge is not the feed, the genetics, or the environment—it is the precision of the information used to make decisions. If biomass is poorly estimated, if growth is not validated, if feed consumption is inconsistently recorded, or if decisions rely on perceptions and averages rather than evidence, the feeding strategy will never reflect the biological reality of the fish. Conversely, when data becomes precise, when growth curves are correctly interpreted, and when critical points—such as the inflection point—are identified at the right moment, decision-making becomes a strategic process and efficiency improves naturally.

At Pinuer Consulting, we help producers move beyond perception and uncover what truly drives performance: reliable measurements, clear protocols, and the reduction of data noise that hides the real story behind production results. When information becomes precise, strategies evolve, efficiency improves, and profitability begins to align with the true potential of the system. And for operations ready to transform inconsistent information into a competitive advantage, we can support the implementation of technical criteria and systems needed to clearly understand growth, feed consumption, and efficiency throughout the production cycle.