The Tunze Osmolator Nano is a great choice for hobbyists with aquariums up to 55 gallons and looking for an Automatic top off system that is simple and reliable.

It utilizes a float switch for water level detection and includes a convenient magnetic mount so you can easily mount the sensor in your sump or your aquarium. A protective shield is also included to help prevent snails and debris from obstructing the float switch.


A small pump, tubing and a return bracket are included which means you do not need to purchase additional parts for installation. It features two anti-overfill settings that limit the amount of time the pump can operate continuously.  This gives you the extra piece of mind because it will ensure your tank cannot be overfilled.

As with many other German-made Tunze products, the Osmolator Nano is quality built and well designed for long lasting operation in your aquarium. You can also check out the Tunze Osmolator standard for larger tank and added protection.