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Tunze Osmolator Universal 3155 Auto Top Off
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  • Tunze Osmolator Universal 3155 Auto Top Off

Tunze Osmolator Universal 3155
Auto Top Off

SKU: 202307


  • good product recommended. By perry on 7/22/2014

    This is a great product by tunze all-around. the only problem I had with the unit is that the metering bump broke shortly after I received the unit. but I contacted tunze and the quickly replaced the pump at no charge.
  • Working great. Shutoff redundency By John on 7/7/2014

    I have been using this in my 75 gallon or approximately 18 months. It has been working flawlessly. I originally had the sensor in my display tank and when I introduced a sump, I moved the sensor into my sump. I am using RO/DI water with no Kalkwasser added. I like that there are two mechanisms to shut off the unit if the level is higher than it should be.
  • The best By Jim on 6/27/2014

    Really not much to say as the product is excellent quality and works. Do yourself a favor and don't cut corners on an ATO.
  • Simple design with a back up switch By mfief on 6/26/2014

    if you read the directions this is fairly easy to set up. I didn't want to spend the money but in the end it has been worth every penny. I definitely noticed a difference in my corals. instead of adding a half gallon of top off water in the morning and at night this does the job several times through out the day without forgetting.

    I love the sensitivity of the optical sensor and the face that there is a back up float valve and alarm as an insurance policy.

    The pump is a little noisy and be careful with the magnets, they are strong and will get more than your attention if you pinch yourself with them.
  • Easy set up By Joshua on 5/28/2014

    Its working great so far. It only took me about 15 minutes to set it up.
  • Awesome! Best I have used! By Cornfedone on 5/5/2014

    I have had ATOs but this one rocks! Easy setup, I am able to keep topoffs to a minimum so not to disturb ph, all, calcium levels.
    All I can really say, is Love This ATO!
  • LOVE IT! By Shawna on 5/1/2014

    I am SOOOOOO happy that I no longer have to tote around gallons of salt water to top off daily That got old really fast and my tank isn't even that big. This little gadget was easy to mount and works perfectly. Several times throughout the day I'll hear it rev up and top off the tank, keeping my salinity from fluctuating.
  • Awesome By Chris on 5/1/2014

    I truly wish i would have made this purchase years ago. It was very easy to install and works like a champ.
  • Perfect By Anneke on 4/30/2014

    I have had this ATO for a couple weeks now and it is so reliable that I almost forgot I have it. It was easy to set, and did not need a break-in period.
  • German product. By waterflyer on 4/26/2014

    Need I say more. This is made in Germany. Extremely high quality product. I actually have mine 20 feet away from my tank and it pumps it with no problem. Horizontally and with only a 4 ft vertical height above the actual pump. Great system, very reliable!

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