Which factor is crucial for maintaining water quality in aquaculture?

Oxygen levels are essential for maintaining water quality in aquaculture because aquatic organisms rely on dissolved oxygen for survival. Fish and other aquatic animals need sufficient oxygen to support metabolic processes, respiration, and overall health. If oxygen levels drop significantly, it can lead to hypoxia, causing stress or even death in the aquatic species being cultured. Ensuring adequate aeration and circulation in the water is crucial for promoting a healthy environment.

The other factors, while they can impact water quality, do not have as direct an effect on the immediate survival and health of aquatic organisms as oxygen levels do. For instance, temperature fluctuations can influence metabolic rates and behavior but are less critical than maintaining adequate oxygen levels. Contaminated feed can lead to health issues in fish, but it does not directly affect water quality itself in the same way that oxygen does. Lighting conditions can impact growth and reproduction patterns but do not directly correlate with the immediate necessity of oxygen for aquatic health.