Tunze Osmolator 3 Auto Top-off

Tunze Osmolator 3 Auto Top-Off – Smart, Stable, and Built for Long-Term Water Level Control

The Tunze Osmolator 3 Auto Top-Off delivers peace of mind with its high-tech water level regulation and foolproof design. Whether you're running a bustling reef or a low-key freshwater setup, this ATO system keeps your salinity—and your sanity—right where they belong.

Tunze Osmolator 3: Reliable Water Stability for All Aquariums

Consistent water levels make or break tank health. The Osmolator 3 ensures nothing breaks—not even your nerves during vacation.

• Smart Salinity Control: Maintains your aquarium’s salinity with laser-like accuracy.

• For Salt or Fresh: Works great on both reef tanks and freshwater systems.

• Plug-and-Play Design: No guesswork. Just install, plug in, and relax.

Compact and Complete (Well, Almost)

It’s an all-in-one unit—except the ATO reservoir. You’ll need to bring your own jug to the party.

• Fits Nearly Any Setup: Mount it in the sump or right on the rim.

• Strong Magnet Holder: Secure the sensor on glass up to 15mm thick.

• Clean Look: The unit stays out of sight and out of the way.

Optical Sensor with Precision You Can Count On

Forget the float switch nightmares. This optical sensor is laser-focused (literally) and built for reef reality.

Features That Just Work

• Pinpoint Accuracy: Measures water levels within 0.5mm.

• Bubble and Scratch Resistant: Keeps working even when things get messy.

• Shielded for Safety: Protection cap keeps curious critters from tampering.

• Thermal Sensor Backup: Stops overfills before they start.

The Turbelle Jet Pump That Powers It All

Small but fierce, this pump doesn’t play around—especially when it comes to vertical lifts.

Pump Performance Highlights

• Delivers Up to 20 Feet: Pushes water to even the tallest tanks.

• Run-Dry Protection: Auto shutoff keeps the motor safe.

• Built-In Blockage Defense: Continues running smoothly, day in and day out.

Technical Specs of the Tunze Osmolator 3 at a Glance

• Sensor Max Glass Thickness: 15mm (0.59")

• Tube Holder Max Thickness: 22mm (0.87")

• Max Delivery Height: 6.2m (20.34')

• Tubing Size: 6mm OD | 3.9mm ID

• Tubing Length: 3m (9.84')

What’s in the Box?

Here’s what you get (and what you’ll brag about):

• Tunze Osmolator 3 Sensor

• Magnet Holder

• Turbelle High Jet Pump

• 12V DC Power Supply

• Tubing and Tube Holder

Final Word on the Tunze Osmolator 3: Automation That Actually Delivers

The Tunze Osmolator 3 is the set-it-and-forget-it ATO solution reefers rely on for daily stability. With smart sensors, a beast of a pump, and a design built for real-world tanks, it’s more than just an upgrade—it’s an essential.

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