Smart Level is the new versatile fully electronic water level controller designed by Hydor safely and easily handles the aquarium and sump water level due to evaporation or drain malfunction. It is designed to be used under the many different conditions that exist in marine and freshwater aquarium environments.Smart Level technology reduces the problems related to lime scale deposits, bacterial film, and wave action, which ensures the continuous, safe, and regular functioning of the Smart Level control. It is fully electronic, with dual alarm providing both light and sound to alert of any malfunctioning in the water levels or the unit. Low voltage. The probe is insensitive to surface movement of the waves. The Smart Level is ultra-compact, stops overflow flooding, works with both freshwater and saltwater, has no moving parts, is easy to install and will maintain a constant water level in the sump or aquarium. A magnet-suction cup support is included to allow free positioning on up to 0.4 inch aquarium glass thickness.