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ATO & Dosing Pumps

An aquarium ATO or dosing pump slowly moves small amounts of fluid to replenish evaporated water or important elements like calcium and alkalinity.

What is an ATO? An aquarium Auto Top-Off system measures water levels in the aquarium or sump. When the automatic top-off sensor detects a drop in water level, a pump sends fresh water from an auto top-off reservoir into the tank.

The best auto top off system, like the Tunze Osmolator, will have multiple sensors and fail safes to prevent flooding. A good nano auto top off, like the AutoAqua Smart ATO micro, has all this in a tiny form factor that fits in an all-in-one nano. A kalkwasser reactor can be attached to an ATO to replenish Ca and Alk in a reef aquarium.

An aquarium doser, like a peristaltic dosing pump, delivers small amounts of fluid in timed intervals. The timer is tuned to deliver elements at the same rate they are depleted. A reef doser setup will often have at least three pumps (for Ca, Alk, Mg).

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