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ATO Systems & Reservoirs

What does ATO stand for? An ATO is an Auto top off system.

Stop pouring water into your tank every day! Heat and water circulation cause aquarium evaporation. The most basic aquarium ATO is a float switch, which turns on a pump to replenish water lost to evaporation.

There are many advanced ATO systems, like the Auto Aqua Smart ATO or JBJ ATO, that use multiple water level sensors. When the water level drops, the ATO sensor turns on a pump sitting in an ATO reservoir. A good ATO will incorporate at least two sensors as a failsafe, so that a sensor failure doesn’t lead to an overflow. For example, the Tunze Osmolator (a best seller) has a mechanical float, an optical sensor, and an electronic failsafe. All of the sensors must fail for there to be a flood.

Use a kalkwasser reactor along with your ATO to raise pH and replenish calcium and alkalinity.

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ReefBreeders Prism ATO Auto Top Off System
JBJ Nano ATO Auto Top Off System with Pump
ReefBreeders EXO ATO Auto Top Off System
Trigger Systems Crystal ATO Reservoir Tank - 10 Gallon
Neptune ATK V2 Auto Top Off Kit

Out Of Stock


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