Dissolved Oxygen (DO) refers to the amount of molecular oxygen dissolved in water that is available for biological and chemical processes. It is a key indicator of water quality and plays a vital role in the survival of fish, microorganisms, and other aquatic life. The concentration of dissolved oxygen is influenced by temperature, pressure, salinity, and biological activity. Low DO levels can indicate contamination, high organic load, or poor water circulation—leading to negative effects on ecosystems and industrial processes. JUMO dissolved oxygen sensors are used in a wide range of applications, including: • Wastewater treatment: Monitoring aeration in activated sludge tanks to optimize biological cleaning processes. • Drinking water treatment: Controlling oxygen levels to prevent corrosion and ensure water quality. • Aquaculture: Ensuring ideal living conditions for fish and aquatic organisms. • Environmental monitoring: Assessing the ecological health of lakes, rivers, and coastal waters. • Food and beverage industry: Monitoring process water to maintain product quality and hygiene. Other fields of application include: • Power plants and boiler feed water • Biotechnology and fermentation processes • Research and laboratory analysis • Cooling water circuits • Hydroponics and greenhouse systems