Water quality management in pangasius catfish farming determines chronic welfare outcomes for billions of fish, with dissolved oxygen, ammonia, and temperature being the most critical parameters.
Pangasius air-breathing capability is sometimes misused to justify water quality conditions that would be unacceptable for obligate gill-breathers, overlooking that chronic suboptimal conditions still cause physiological stress and welfare compromise even when they are not immediately lethal. The ability to supplement oxygen uptake with air breathing is an emergency adaptation, not a license for permanent hypoxic conditions. Farms that maintain good water quality through appropriate exchange, aeration, and density management produce fish with lower stress indicators, better growth efficiency, and reduced disease burden — all reflecting genuine welfare improvement alongside commercial benefit. Certification-driven water quality standards represent one of the most practical mechanisms for improving pangasius welfare across the enormous scale of this industry.