“Osmolateur” is best translated as **“auto top-off system”** or **“automatic water top-off device”** in English, especially in a

Automatic top-off systems for aquariums

The automatic top-off system emerged alongside the growing demands of marine aquariums, where evaporation directly affects salinity stability. Initially used in aquaculture and professional installations, it quickly became essential equipment in reef aquariums.

Its role is to automatically replace evaporated water with purified water, thereby maintaining a constant density without manual intervention. Modern systems rely on reliable optical or mechanical sensors, along with overflow protection safeguards.

By ensuring stable salinity, the automatic top-off system reduces stress on organisms and improves parameter consistency. Today, it is an indispensable tool for precise, safe, and convenient maintenance of a marine aquarium.