Today we will be talking about the Tunze Osmolator Nano 3152 Auto Top Off (ATO) System!

In marine aquaria, keeping stability of your water chemistry is absolutely crucial to the life and health of your reef tank inhabitants. For this reason, an automatic top off unit—or ATO—is an essential part of your aquarium gear. As water evaporates from your aquarium, the ATO replaces the evaporated water with fresh water from the nearby reservoir in order to maintain the stability of your reef’s water chemistry.

When it comes to ATO’s, Tunze is one of the most trusted names in the hobby—and with good reason! They literally invented the ATO 30 years ago and have been continuing to perfect it ever since. Tunze’s flagship ATO is the Osmolator 3155, and today we are reviewing the Osmolator’s little brother, the Osmolator Nano 3152.

The Osmolator Nano comes with many of the popular features that have made the Osmolator 3155 one of the bestselling ATO on the market—yet in a smaller version that’s more suitable for smaller tanks where space is prohibitive.

Except for the reservoir, everything you need is included to get your Osmolator Nano set up in around 5 minutes. It comes with the pump, fill hose, hose mount, processor, float switch sensor, sensor shield, mounting magnet, and power supply.

The Osmolator Nano is powered by the same small-but-powerful DC pump as the larger Osmolator 3155. This pump is designed with a maximum head pressure of 13 feet (4 meters) although Tunze does not recommend using the Osmolator Nano to deliver water more than 10 ft (3 meters).


Learn more about the Tunze Osmolator Nano 3152 Auto Top Off System, read user reviews, ask questions, and purchase a unit for your aquarium at Marine Depot:

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