The standard for smaller tanks By Join the Revolution on 5/11/2017
Join the Revolution would recommend this product to a friend
Tunze quality on a smaller package. These are bullet proof top off units. Those who have problems are not reading the instructions and have it installed in an incorrect area. You get a two year warranty on this brand. Who else does that? Nobody.
Great simple solution for top off By Todd on 5/5/2017
Todd would recommend this product to a friend
I've used this top off system for over 2 years now. I never have any issues with it.
Most of the complaints I see people are mentioning they have to unplug it and plug it back in.
This is actually a feature to prevent a disaster. If the pump runs longer than 3 minutes it has to be reset. Under normal operation this never occurs. However if the sensor were to get stuck this feature would prevent the system from pumping until it was out of water. Normally mine only runs for less than 10 seconds at a time.
The other procedure that requires you to unplug it is when your reservoir runs dry. I assume this is to prevent the pump from burning out.
An on/off switch would be nice to make these "reboots" easier, but it's not much of a hassle to take the plug out for a second or two.
Good for the price By Doug e fresh on 4/10/2017
Doug e fresh would recommend this product to a friend
I have only used this for a month and it has worked well. The only problem I have is I don't quit trust the single float switch.
But time will tell if I learn to trust it.
Not typical Tunze quality By Mark on 2/27/2017
Mark wouldn't recommend this product to a friend
Bought this thinking I would be getting the same quality as it's big brother, but this one is complete garbage. The pump has failed on me several times, requiring me to unplug it and plug it back in. Luckily I caught it quickly each time, but I definitely wouldn't trust this if I went on vacation. Also, unlike it's big brother, this ATO only has one sensor (a float sensor) that is prone to getting stuck. I would recommend only getting the bigger osmolator or using a different brand that uses an optical sensor.
Pump Issues By Matthew on 2/23/2017
Matthew wouldn't recommend this product to a friend
There appears to be issues with pump quality of these units. The pump that shipped with my nano could only develop about 2 inches of head.
Tunze sent me a second pump which seems to be ok.
NOTE TO CANADIAN CUSTOMERS: You may have issues with warranty processing in Canada. Tunze Canada will not honor warranty on products purchased in the US, Tunze USA will only cover the parts and labor on products in Canada due to expensive shipping costs to Canada.
Would not recommend By Wilson on 12/12/2016
Wilson wouldn't recommend this product to a friend
I bought this with the idea it would make my life easier. The first pump failed and Tunze replaced it. The second pump ran great for @ a week then stopped filling up the tank unless I unplugged it and plugged it back in. They are now sending a third pump however I'm not holding my breath. Had I known this would happen I would have purchased another model.
Excellent product By Richie D on 11/4/2016
Richie D would recommend this product to a friend
Sure is convenient not having to add to-off water all the time. Just went away for the weekend and didn't have to worry about whether or not the gravity fed system I had always used would work or not. Many times I would come home to find the pump sucking air and the aquarium down about 4 inches. Not this time! While it is very expensive, it does save a lot of headaches and potential loss of fish and corals. Absolutely recommend it.
Great mini version of the bigger ato By Sgt Harold on 9/13/2016
Sgt Harold would recommend this product to a friend
I brought this for my Red Sea max 250 rimless . It has a small tank that I use a 5 gal bucket to keep full. Keeping salinity if important in maintaining a stably ecosystem .
Part #4017.000 Controller Osmolator nano device By Max on 8/3/2016
Max wouldn't recommend this product to a friend
I have written to the company in Germany to try to get a new part #4017.000 Controller Osmolator Nano device. I have to unplug the device and reconnect it every cpl days to get the unit to work properly to top off. It makes a noise like it wants to pump water to my reef tank but will not until I unplug the device and re-connect it then it works for a day or two. I hope I can get a replacement part as I only bought this from BRS beginning of July last month. I sent the scan of my invoice to the company in Germany as well so waiting on a response.
Great By darryl hey on 8/1/2016
darryl hey wouldn't recommend this product to a friend
have 3 of these on nano tanks 29 biocube 40 breader and 45 cube works great! have been running for 2 years now