Pump is the weak link By Marc on 1/17/14
Marc wouldn't recommend this product to a friend
It's a shame, but the pump they use for this system is cheap trash. I'm on my third replacement is only seven months.
Never Fails By Scott on 1/9/14
Scott would recommend this product to a friend
After seeing a video of Ryan talking about it, I purchased one and would not use anything else at this point. My water level changes very little before this thing kicks on giving ultra stability in my SG. Had mine for a year and have had absolutely no issues with it. The pump is always submerged in kalk and hasnt failed yet. I have a spare on hand just in case though.
There is a breakin Period By Jared on 1/6/14
Jared would recommend this product to a friend
At first I thought I had a issue. I have come to find out that all Tunze ATO units with the optical sensor need a "break in" so the bubbles won't interfere with the level reading. I soaked the optical sensor in vinegar for 5 hours, cleaned off, and mounted. I havent had a level sensing issue since. I am currently using this with Kalk to top off my 65 Gallon system.
love it By trent on 12/28/13
trent would recommend this product to a friend
no more carrying buckets through the house. easy to install. keeps my refugium at the same level day and night. keeps salinity steady.
the electronic eye is the best part. nothing to get stuck. great product.
Do not hesitate... just get this! By Easiest install ever on 12/19/13
Easiest install ever would recommend this product to a friend
I used to have to fill about 2-3 gallons per day into my 120 gallon system, now I just keep my reservoir filled up, topping it off about once every week or two. This is well worth the price. No idea what the other reviewer was saying about a break-in period. Worked instantly, and has been working fine ever since.
Has a break in period By Michael on 12/16/13
Michael would recommend this product to a friend
Easy installation. However, it overfilled and the alarm went off. I have read it has a break-in period so I hope this to be the case. I even washed the sensor before install.
Great Product By Dustin on 12/12/13
Dustin would recommend this product to a friend
This top off was very easy to install and has been working flawlessly.
Marine Hobbyist Must Own!!! By BuckeyeFrags26 on 12/12/13
BuckeyeFrags26 would recommend this product to a friend
I currently have one on each one of my tanks. One heck of a product, nothing else to be said about it. The company name says all you need to know when it comes to quality equipment. By far the best NO Instructions needed system. But if it's your first one you own, atleast read the instructions, it does have informative information you do need to know.
Better than my old JBJ ATO By ToledoNate on 12/10/13
ToledoNate would recommend this product to a friend
I used the JBJ ATO for the first year of my tank. I have a 2.5 gallon jug for my ATO and I would find the whole jug emptied and the water level in my sump far higher than my float line. My protein skimmer needs to be in a constant depth of water and would over flow when the ATO failed in the off position.
My new Tunze Osmolator is great. It keeps a perfect level in my sump and my protein skimmer has never worked better. I especially like the Tunze because it pumps a fairly consistent amount of water every time it turns on, allowing me to more accurately dose Kalk in with the ATO.
Oops forgot to read instructions! By BigMo on 12/8/13
BigMo would recommend this product to a friend
Never needed instructions! Works with in 30 seconds after plugging in. 1 minor level adjustment and topped off right to the full line. Checked the alarm by sliding float up and loud and clear. One of the coolest toys for my 55 gal I've invested in. No more gallon jugs filling up the sump for me!!!!
Works By Martin on 12/6/13
Martin would recommend this product to a friend
This auto top off works for me. the only think I found odd is that when I replug it in after a water change, it starts up for about 30 seconds even though the sensor is submerged. I just hold a cup under the outlet for that 30 seconds to collect the extra water. After the initial plug in it works fine.
Solid Product By Jim on 11/19/13
Jim would recommend this product to a friend
This is my 1st ATO system I purchased. It really makes life so much easier. No more filling sump everyday and my salinity stays constant. I hooked it up with a 10 gallon ATO tank from Advanced Acrylics and it works great. Very well built. The only complaint is the pump is a little loud but not a huge deal.
Great Product By Troy on 10/30/13
Troy would recommend this product to a friend
I have only used a couple of ATO systems and this is far superior to others. It's well worth the extra money. My previous ATO used dual float switches that would calcify or be affected by turbulence in the sump. This is spot on every time. I have a larger system 300 gallons so the pump being able to run for an extended amount of time is great. I also like that the pump will automatically turn itself off after a certain amount of time as another added precaution
Great Quality! By Jorge on 9/8/13
Jorge would recommend this product to a friend
I have to say that this system has made my life much better! I don't have to worry about adding fresh RO/DI water every other day due to evaporation, it keeps my water at the perfect level and creates a much more stable environment for my fish.
The system was incredibly easy to install and it works perfectly. This will be the only top off system I will use on future tanks.
If you need a top off system... buy this unit and don't compromise on anything else!
Great Reliable Product By Ryan on 8/26/13
Ryan would recommend this product to a friend
Best ATO in my opinion, very accurate and simple to set up. The initial set up was easy but had a little trouble with bubbles covering the optical sensor causing it to overflow and make the float valve go off. I turned it off and let it sit in the water for a few hours, then plugged it in and has worked ever since.
A little spend, but a crucial part of the aquarium
A good product that could use a little refining. By Matt on 8/15/13
Matt would recommend this product to a friend
Overall I found this product easy to set up and install. Once properly set up, this has kept the water levels in my sump very stable.
I do have a couple of small complaints though:
1) I wish the instructions had come right out and said to place the primary sensor in an area of the sump with NO, and I mean NO, air bubbles rather than telling you that in the trouble shooting section.
2) A better mounting system for the controller. A couple of stick on pieces of Velcro? A simple mounting bracket or even molded screw holes would be better.
3) The LED indicators are unshielded and impossible to read unless you are looking at the controller straight on.
Honestly, where is the much hyped "German quality and attention to detail?" For $200+, I would think Tunze could do better.
Best ATO money can buy By Joe on 8/13/13
Joe would recommend this product to a friend
Great product. Exceed expectations. Even though it's a little pricey but it does come with the pump so that make it reasonable. Very acurrate and trustworthy. I expect it to work a long time.
Quality product By Sal on 7/21/13
Sal would recommend this product to a friend
This was very fun and simple to install. It works flawlessly.
Reliable and effective By Andrew on 7/20/13
Andrew would recommend this product to a friend
I have had this running a few months on my 80 gallon reef. The unit was relatively easy to set up, the instructions are just poorly laid out. Once set up there were no issues and it has been keeping my water level consistent.
Well worth the price!!!!!!!!!!! By jhmeresqu on 7/8/13
jhmeresqu would recommend this product to a friend
I utilized it as my ATO for my RO/DI water return to sump system to replace evaporated water. Works great , love the fact that it has the Sensor Eye and the backup float switch. Can't get enough redundancy. A little pricey but well worth it.
Great investment By Mpek on 6/30/13
Mpek would recommend this product to a friend
All I have to say is that this system makes my life a lot easier! As long as I keep my ATO container full it runs flawlessly. I would recommend this to anyone.
Not bad By Shalashaska on 6/29/13
Shalashaska would recommend this product to a friend
I've had it so far for 3 days. The set up was easy. I dident have to use the instructions what so ever. The only thing I found so far that is a issue is that micro-bubbles from my protein skimmer like to settle on the optical eye, thus giving a false water low indication. I just moved it to a better location, problem solved.
Great But there is a break in period. By Will on 6/26/13
Will would recommend this product to a friend
So for the first 3 or 4 days the "eye" sensor has a hydrophobic film which will make the sensor think it is in the air and will continuously pump water until the float switch will shut it off I recommend you leave the sensor in the sump for 2-3 without turning it on that will resolve these issues.
Overall nice ATO By PMK on 6/17/13
PMK would recommend this product to a friend
I am pleased with this ato unit. I had some issues with the pump just kicking on and staying on. Dropped 2L of rodi into the system and stopped when the float kicked in. I couldn't figure it out and thought I might have a bad unit. So broke it down off my display and set it up on my mixing tank. The same thing happened. So ran through the set up again and disconnected the pump from the power supply wires and connected them up again. That did it. The pump no longer kicks in and stays on. Haven't seen this in other reviews or the Tube but did see a review about a weird first hour break in period. Guess it was the connection or the break in period. But its been on my display for a couple weeks now and has kept the water level very stable. Been monitoring the salinity and everything has been real stable. I think it will be a long term success. I agree with some other reviews that it seems a bit delicate for a couple hundred bucks.