Glossary
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
ATO unit + reservoir. AutoAqua Micro for nano, Tunze Osmolator for mid-size.
AutoAqua Smart ATO Micro
Best small-tank ATO. Dual-optical sensor failsafe.
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Tunze Osmolator 3155 ATO
Mid-size ATO with optical + float failsafe.
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Rubbermaid Commercial Brute 14 gal container
Standard ATO reservoir. Food-grade plastic.
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