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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


  • functional and efficient By Steven on 9/8/2014

    I have used the Tunze for two years now and it meets my expectations. One needs to take seriously the caution to not have the feeder hose under the surface of the aquarium water level. I flooded my office twice doing just that. Also, the pump has a 6 month to a year longevity and they go out without much fan fare. Keep a couple extra pumps, at 23 dollars, on hand. My final caution is not a fault of the unit but I have an auto feeder in my lower tank and when the feeder was too close to the optical sensor flakes of food caused the unit to think the tank was at level and it failed to fill. Keep the food as far away from the sensor as possible. Beyond these concerns, it is a great unit and very dependable.
  • Gold Standard of ATO By Keith on 9/4/2014

    The system comes with everything you need to get an ultra-reliable and well built auto top off system in place on your aquarium. This is a must if you want to keep your parameters consistent and your tank running as it should. Make sure and put the rubber feet on both halves of the magnets to keep them from sliding around. I love the redundancy of an optical eye, a mechanical float switch and then a timer on the pump.
  • makes reefing easy By matthew on 8/23/2014

    This auto top off makes my life easy, I have had it for over a year now and have never had a problem.
  • Wonderful product that has made my life easier By David on 8/15/2014

    I was a little skeptical at first installing an auto top off. I had fears or dumping 30 gallons of fresh water into my tank with a faulty device or switch. Having this up and running now for awhile has been great! The sensor is very sensitive and adds small amounts of water throughout the day. I also like the back up float switch. It was easy to set up and the magnets make adjustment simple. I now fill my top off container every several weeks and that's all! One piece of caution is to watch the placement of the top of container as you can get a siphon started. Great product!
  • Phenomenal! By MCHERRI on 8/5/2014

    I purchased this device a year ago and I cannot begin to explain how wonderful it has been since. No more daily top off. Now you can just sit back and enjoy your aquarium. Coupled with an automatic feeder, you'll spend less time worrying about your fish and coral, and more time enjoying your tank!
  • Great Pruduct By Crysos on 8/4/2014

    I got this about 3 months ago and it is great! Easy setup and it keeps my water where it needs to be. I am home and watching my tank all the time but this is just a great tool to help with top off!
  • 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.

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