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Home » Saltwater Aquarium Supplies  » Dosing Pumps & Top-Off  » Electric Powered  » Plug-In Units  »  Hydor Smart Level Control ATO System
Hydor Smart Level Control ATO System

Hydor Smart Level Control ATO System

Average Rating 3.5 22
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Hydor Smart Level Control ATO System Information

Product Manuals & Documentation

Hydor Smart Level Control - water level management system

Smart Level is the new versatile fully electronic water level controller designed by Hydor. Smart Level safely and easily handles the aquarium and sump water level due to evaporation. Designed to be used in the many different conditions that exist in the marine and freshwater aquarium environment. Smart Level technology reduces the problems related to lime scale deposits, bacterial film, and wave action, which ensures the continuous, safe, and regular functioning of the Smart Level control.

For the SMART LEVEL Control, all types of pumps can be used, up to a maximum power of 50W. Choose a pump with a flow and head suitable for the type of use. Note that it is best to use a pump that tops off slowly within 10 minutes (maximum topping-off time).

Top-off pump required and sold separately.

Units now include a polarized socket and will accept a standard 2-prong plug.

Manufacturer Info

Hydor has been producing a comprehensive range of equipment for aquariums and ponds since 1984 and offers the best in high-technology for the creation of a living ecosystem at home. The factory has developed thanks to the engineering competence of its founder and its continuous growth is based on the investment it has made in research and the development of innovative technical appliances. A competitive and dynamic structure of more than 150 employees regularly engages in the implementation of products which meet the demands of 50 nations and keep pace with the evolution of the world markets. The global quality is not a simple working method but a daily expression of mind.

Hydor Smart Level Control ATO System Reviews

Average Rating
(22 reviews)
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of 3

Hydor ATO

Reviewers Rating Excellent!

Posted: 9/28/2016 from Monroe, GA UNITED STATES
5.0 5
Experience Level: Beginner

Comments: So far the ATO has worked flawlessly. I really like the display letting me know if we are on the Low side or high. Either way the audible alarm provides a warning.

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Not Sending Water

Reviewers Rating Unsatisfactory

Posted: 8/22/2016 from CARNEGIE, PA UNITED STATES
0.5 5
Experience Level: Intermediate

Comments: I have had this for about three months. At first it worked very good. Now I am having a problem with the sensor tell it to send water into the tank. The pump is clean and each day I use a tooth brush to clean the sensors in the tank at water level. I have reset this and tested by moving the sensors about water to cause it to turn the flow on and it does not work. I am in no way calling the company knowing from many articles how they treat people. I have also read how many use four stars and the majority have problems. This means it is a shot in the dark to get a good one. Customer service is the main thing in our hobby. This company deals with volume and does not consider the customer. The system is sealed and looks like it should work well but there are too many problems to recommend it. I would not recommend it knowing many other good ATO systems out there.

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Too Slow to Switch off

Reviewers Rating Average

Posted: 5/27/2016 from West Coast
2.5 5
Experience Level: Expert

Comments: Using this on a 25 gallon sump to top off my 135 reef, the sensor is too slow to react and tends to fill sump too fast, even with a super small little Desk Type water fountain pump that pumped maybe 1 gallon a minute. the submersible sensors need different vertical spacing to allow a lower dead-band of switching, or make the sensor thermalcouple be more timely to switch. I'm going to try it on a 40 gallon sump next. but right now it's gather expensive dust as a lesson learned.

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Failed Electrodes

Reviewers Rating Below Average

Posted: 3/22/2016 from NEWMARKET, NH UNITED STATES
1.5 5
Experience Level: Intermediate

Comments: Electrodes failed causing overflow of top off water. Didn't have it for that long. worked ok for a while but when the electrode failed the whole thing becomes useless.

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Reviewers Rating Excellent!

Posted: 12/28/2015 from MODESTO, CA UNITED STATES
4.5 5
Experience Level: Expert

Comments: Now this is my first auto-top off unit and I must say for the price I am very impressed. It works very well and it's reliable. Hydor always delivers. The only thing that bugs me from time to time is that if the sensor isn't level to the water like if it's tilted just a bit it starts to beep until I get it right. But again I move my sensor quite a bit and its in a hard to reach place. With that said once you place the sensor and leave it alone you won't have any problems. Definitely worth the price. Much better than those more expensive auto top-off units.

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Excellent ATO system

Reviewers Rating Excellent!

Posted: 2/12/2015 from CONYERS, GA UNITED STATES
5.0 5
Experience Level: Expert

Comments: I did a few months of research on different ATO configurations and products before I purchased this. I've had this ATO system in place and running now for about three weeks and couldn't be more pleased. The setup is straight forward and their user manual was actually descent. It has been topping off my sump with a gallon of RO-DI water every other day without any issues. It's really nice not to lug buckets of top-off anymore, after 4 years of doing that whole routine. If I could change one thing it would be moving the Alarm level sensor up just a tiny bit more, or if Hydor engineered that sensor to be manually adjusted up or down, that'd be great. On occasion I've noticed that when I dip out 3 or 4 cups of water to thaw out cubes of Mysis shrip, when I pour it back in my sump level rises and immerses the alarm sensor for 5 or 10 min. This is just a characteristic of my sump and plumbing, not really the fault of Hydor's design, but allowing the alarm sensor to move upwards a bit more would solve that issue for me. Overall though, I'm very pleased with this product. Monitoring multiple temperature sensors and timing the return pump shut-on and shut-off are not trivial tasks. Their design performs these tasks gracefully.

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Reviewers Rating Excellent!

Posted: 12/1/2014 from MORRISTOWN, TN UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I love this ato so easy to was a plus arrived on time as marine depot said it would. .

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buyer beware!

Reviewers Rating Unsatisfactory

Posted: 6/16/2014 from Woodbridge, VA UNITED STATES
1.0 5
Experience Level: Intermediate

Comments: I have had nothing but difficulties with this product. It has overflowed my sump every time I let it run on auto. I clean the sensor and follow the trouble shooting guide. Look somewhere else.

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better than JBJ

Reviewers Rating Great

Posted: 6/10/2014 from SOUTH GRAFTON, MA UNITED STATE
3.5 5
Experience Level: Beginner

Comments: So far so good, better than JBJ version. Only thin is the clear plastic part that attaches the level switch to the magnetic mount doesn't hold the sensor. Broken in the box- needed modification to work.

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Great Product

Reviewers Rating Excellent!

Posted: 5/28/2014 from Roswell, GA UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: Replaced a Tuntz with the Hydor ATO. The Hydor was much easier to set up. Looks like it is well made, and was a lot less expensive. Time will tell, but overall I am very happy with the Hydor system.

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