Tunze Osmolator 3 Auto Top Off

The Tunze Osmolator 3 (3154.000) replaces evaporated water automatically. It combines an optical level sensor with an independent thermal safety sensor and a 10-minute pump timer for additional protection.

Check the fit

• Sensor magnet: fits glass up to 15 mm thick.
• Tube holder: fits edges up to 22 mm thick.
• Maximum delivery height: 3 m (9.84 ft) in standard mode or 6.2 m (20.34 ft) in boost mode.
• Reservoir opening: allow at least 75 mm for the standard pump connection.

Included in the system

• Optical sensor assembly with protective cap and magnetic mount, including an independent thermal safety sensor.
• Turbelle High Jet top-off pump, 12 V power supply, 3 m of tubing and a tube holder.

What you will need

Provide a separate top-off reservoir and suitable freshwater. For marine aquariums, evaporation is replaced with freshwater, not mixed saltwater. Mount the sensor where the water level changes with evaporation, such as the sump’s return chamber, and position the delivery tube as shown in the manual to prevent siphoning.

Care and warranty

Check the sensor regularly and clean it as directed. Tunze’s general limited warranty is 5 years for materials and workmanship; wear parts such as pump drives and bearing washers have 2-year coverage. Refer to the manual for conditions and regional terms.

Manufacturer resources

• Tunze Osmolator 3 product page
• Setup, parts, comparison and warranty manual (PDF)