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Tunze Osmolator Aquarium Auto Top-Off System

Water level regulation with static sensors

In 1983 already, TUNZE Aquarientechnik introduced the first water level regulator (Osmolator) to aquarism. TUNZE Aquarientechnik has developed a new generation of osmotic regulators with static and compact sensors in IR technology for constant water level regulation in freshwater and saltwater aquariums. It ensures osmotic stability in freshwater and saltwater aquariums by precisely and regularly compensating the evaporated water.

Tunze Osmolator Systems can be used as a supplement in cabinet filter plants, Comline quick-run filters or directly on the tank edge.

(1) The precise water level is ensured by a non-wearing optical sensor and a transistor switch without any moving parts. This sensor is insensitive to soiling, light or magnetic fields.

Its “automatic eye” recognises the water level precisely, even small waves or level variations cannot irritate the unit.

(2) An independent safety sensor with a separate power supply circuit and relay control ensures reliable overflow protection.

(3) An electronic time controller and current limiter for the pump connected result in a higher operational safety. This unit protects the metering pump against running dry and reports an empty storage container.

(4) All functions are clearly displayed by LEDs; safety messages are also indicated by acoustic signals.

(5) The osmotic regulators are all operated at safety extra-low voltage.
Reef Aquarium
Reef Aquarium
Osmolator Universal 3155

Water level regulator with two sensor holding devices, extension and numerous fastening accessories. It is suitable for cabinet filter plants in TUNZE Comline filters or on the edge of the aquarium.

This osmotic regulator can also be used in TUNZE SYSTEM cabinet filter plants. The sensors can be stuck to glass surfaces or can be fitted directly to the edge of the tank.

Delivery condition: Ready for mounting with power supply unit, metering pump, hose, sensor holding device.

Metering pump capacity: 2.95ft: 13.74gph, 4.92ft: 12.42gph, 6.56ft: 7.13h, Hmax: 7.22ft

Warranty: 1 year from date of purchase.

Tunze Osmolator Universal
Item #DescriptionModel #Price 
TZ4111Tunze Osmolator Universal 31553155$199.99
Reef Aquarium
Reef Aquarium
Nano Osmolator 3152

Water level controller with only one sensor for nano aquariums or small aquariums with up to 200 liters (55 USgal.).

Can be installed in a cabinet filter or directly on the aquarium edge.

Scope of delivery: ready for installation with 11V power supply, low-voltage metering pump, 3m (118 inch) hose, magnet holder for up to 10mm (3/8") glass thickness and a protective cover for the sensor.

Tunze Nano Osmolator
Item #DescriptionModel #Price 
TZ4114Tunze Osmolator Nano 31523152$99.37
Osmolator Accessories and Replacement Parts
Calcium Dispenser 350x140mm

The addition of calcium hydroxide (also known as kalkwasser or lime water) is a common method of increasing the calcium level in saltwater aquariums. The calcium hydroxide is dissolved in a separate tank by means of the water jet of the metering pump in the osmotic regulator(s). The lime water is then released into the aquarium in small quantities in regular intervals. The calcium dispenser is fitted between the metering pump and the infeed hose. All TUNZE Osmolator, Osmomat and osmotic regulator sets can be used. The calcium dispenser can also be installed in every water storage tank. The dispenser tank should be topped up with calcium hydroxide every one to two weeks.

The calcium dispenser and the turbo calcium reactor can be combined well with each other. An especially well set pH stability is achieved during the day as well as at night. An increase in performance can be achieved for a larger consumption.

Delivery condition: Reactor, calcium hydroxide fill, holding device and connections to Osmolator, suitable for up to approx. 132 gallon aquariums with stone corals.

Tunze Calcium Dispenser

Storage container 27 L

Container with a contents of 27 l (7.1 US Gallons); large cover opening to facilitate topping up and cleaning. Size for an open 158 gallon tank: fill lasts for approx. one week ø 34 x 43.5 cm

Tunze Storage Container
Replacement Metering Pump

Replacement dosing pump with low voltage 3-12V DC for osmolator, power with 4mm hose at 11V: 0.9m – 110l/h, 1.4m – 80l/h, 1.8m – 58l/h, Hmax 3.6m.
Tunze Replacement Metering Pump
Switched Socket Outlet

In the Osmolator®, the enclosed low-voltage centrifugal pump can be replaced by this switched socket outlet in combination with a more powerful pump. The switched socket outlet can be used to switch metering pumps with 230V (115V), max. 1,800W (900W), such as Turbelle® e-jet 805, 1205, Silence 1073.02, 1073.04 or a peristaltic pump.
Tunze Replacement Metering Pump
Item #DescriptionModel #Price 
TZ4113Tunze Osmolator Calcium Dispenser 50745074$94.98
TZ4117Tunze Osmolator Storage Container 27L (7.1 Gal) 5002.2505002.25$25.99
TZ4115Tunze Osmolator Replacement Metering Pump 5000.0205000.02$23.49
TZ31504Tunze Switched Socket Outlet for Osmolator Auto Top-Off System3150.11$70.12

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