Auto Top Off (ATO) Systems

An auto top off (ATO) system replaces the fresh water your reef tank loses to evaporation, keeping salinity steady without daily topping up by hand. Stable salinity is one of the simplest ways to reduce stress on corals, fish and invertebrates, and it protects your protein skimmer and return pump from swings in sump water level.

This range covers complete ATO kits such as the Red Sea ReefATO+ and Mantis Smart ATO, plus the ReefCan reservoir, ReefControl ATO module and ReefSense sensor for building out a Red Sea system. Fill your ATO reservoir with clean RODI water – never saltwater – and check the sensors regularly. Not sure which setup suits your tank? Contact our Wiri, Auckland team for advice. We deliver throughout New Zealand.