The Aqua Medic aqaniveau is an automatic refill that adds evaporated water from a storage tank. This automatic replacement has been proven especially in sea water aquaria to avoid variations in salt density which are disadvantageous to the aquarium population. But also for fresh water aquaria without any cover or aquaria with open filter tanks should be equipped with an automatic refill system. The refill water is either added via an appropriate pump from a separate storage tank or via a reverse osmosis unit which is controlled by a solenoid valve. The latter is only recommended if quantities of more than ten litres of water per refilling process are required. The device has two operating modes: 1. as a refill controller with one or two switches used to refill evaporated water. One switch controls the refilling, the other works as protection to prevent the pump from running dry. 2. As min./max. contact for the control of osmosis units, in conjunction with a solenoid valve. Please choose between the version aquaniveau with one, or two switches (1 Schalter, 2 Schalter). Attention: the opertaing modus 2 needs two switches!Do you have questions about this article ?