Water quality parameters including oxygen levels, temperature, ammonia, and pH directly determine whether farmed fish experience chronic stress or healthy physiological function.
Fish are often thought to be buffered from environmental degradation by their aquatic medium, but poor water quality is a direct and powerful stressor. Fish in low-oxygen, high-ammonia water experience a physiological stress response equivalent in severity to painful stimuli. Chronic exposure to suboptimal conditions is a form of sustained suffering that may affect hundreds of millions of farmed fish globally. High standards for water quality management are therefore central to any genuine fish welfare program.