ATO
/A-T-O/
Auto Top-Off. Adds RODI water to replace evaporation.
Salinity rises as water evaporates (salt stays). ATO maintains salinity by replenishing fresh water. Two-sensor (optical + float) failsafe is mandatory — single-sensor failures have flooded living rooms.
Recommended
Affiliate linksATO unit + reservoir. Both run two independent sensors: AutoAqua Smart ATO Duo for nano, Tunze Osmolator for mid-size.
AutoAqua Smart ATO DuoTwo optical sensors in one small housing. The nano ATO with a real backup.View on Amazon →Tunze Osmolator 3155 ATOMid-size ATO with optical + float failsafe.View on Amazon →Rubbermaid Commercial Brute 14 gal containerStandard ATO reservoir. Food-grade plastic.View on Amazon →
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