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Tunze Osmolator Universal 3155 Auto Top Off

$189.99 was $ 229.99
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High-tech -- for a reliable water level in the aquarium
In 1985 TUNZE invented the automatic refill system for aquariums. At that time, some people regarded this invention as a useless accessory.... but they forgot something very important: sensitive aquarium animals need a constant osmotic pressure within their cells. The Osmolator (osmotic regulator) is very easy to install and provides its complete functionality in a single compact unit. Only the Osmolator is able to provide you with the necessary security and reliability, since it is based on the vast experience that TUNZE® has been able to gather throughout the course of many years.
The Osmolator will be supplied with low voltage pump, mounting magnets, tubing controller and power supply. You only need a reservoir and water.
The Controller 5017 displays all functions optically and sounds an alarm in case of failures.
Redundant security: the main sensor is a proprietary optic sensor. In case of occuring problems, a safety float switch shuts the unit off and sounds an alarm. Even if that fails, safety circuitry shuts off the pump
after 10 minutes.
-An optical mini sensor recognizes the water level precisely.
-Easy to mount by Magnet Holder.

Customer Reviews

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Truly the ATO bible of this industry Jul 8, 2016
Unless Tunze reinvents the wheel, this top-off unit, IS.... the most reliable -hands down, ATO workhorse in the industry. Tunze's 3155 does not need an aquarium controller to operate continuously- BONUS for you newbies!!
The 3155 is as reliable as your mom (while you were an infant- hopefully). This crucial piece of equipment can make or brake a success vs. failure set up with salinity stability.(stable people, keep it stable).
The unit guarantees a two year warranty along with class A customer service and German engineering.(no brainer).
What else do you need? Save up, buy it. Set it, and as they say "forget it". Thanks to Premium Aquatics for carrying the most recognized and trusted top off for us hobbyist!
Only ATO i WILL TRUST! Feb 11, 2018
In my opinion, the TUNZE 3155 is by far the best ATO system! I have been running 3155 for over 2 years and not ones the TUNZE ATO has failed on me! highly recommended..
3155 Tunze Osmolator

3155 Tunze Osmolator