DESCRIZIONE
The aquarium (1) has a magnetic valve (30) for controlling carbon dioxide supply and comprising a coil to shift the magnetic valve against restoring force by producing reluctance force on a mobile anchor such that the magnetic valve is opened or closed. A flywheeling diode is switched parallel to the coil. The coil is connected with a voltage supply i.e. local alternating voltage system, by a diode such that the flywheeling diode and the diode exhibit transmission directions that are arranged against each other. The coil exhibits measured inductivity. An independent claim is also included for a method for controlling carbon dioxide supply to an aquarium.