Nice ato By Ryan on 3/6/14Ryan would recommend this product to a friendI've had this top off running on my tank for about 6 months now, i can say it works great but has a couple of flaws. The electronic eye can slime over somewhat easily if you don't watch it. Secondly, if the water level in your top off reservoir is higher than the outlet of the pump tube it will create a syphon and drain the whole reservoir into your sump. I've had it almost overflow twice, now i use a 5 gallon bucket on the floor which lasts about a day :( . Overall a great product, a little $$ though.
Best ato By Bryce on 2/25/14Bryce would recommend this product to a friendThis ato is the best one i've ever owned. Never failed!worth the extra cost!
Great Product By Jesse on 2/21/14Jesse would recommend this product to a friendEasy to set up and works great
Best ATO ever By Jonathan on 2/4/14Jonathan would recommend this product to a friendI was a bit put off by the price of the Tunze Osmolator ATO, but when it went on sale at Thanksgiving I went ahead and took the plunge, and I have rarely been so pleased by a piece of equipment! The instruction manual if very helpful, without much useful info lost in translation. Setup was easy, and after on minor overfill due to me not having the two sensors far enough apart, my sump level stays within about a half inch of the same point at all times. I strongly recommend that anyone considering an ATO buy this system. You get what you pay for, and in this case its the best ATO on the market.
Plays well with fish, but requires supervision By cp on 1/28/14cp would recommend this product to a friendOverall this ATO works really well. It's nicely made and it was fairly easy to set up.
Four stars because the sensor got filmed over and stopped working within a week. It was easy to clean by wiping it off and then it worked fine again. The film was my fault, since I hadn't gotten the dosing dialed in the new tank, and I caused precipation by adding Ca and alk solutions to the sump. But even so, it means that the unit is not maintenance free so I will have to get my tank sitters to check the water level and will have to explain how to clean the sensor if needed. Kind of a bummer, since ease of fish-sitting was one main reason for buying this unit.
nothing but problems By Greg on 1/17/14Greg wouldn't recommend this product to a friendI switched from a JBL after the hrs video, and although the pump on the unit is quiet, and moves a lot of volume, I have had nothing but problems maintaining my aquarium salinity. The Tunze will constantly over fill the tank, and the alarm will go off. If I wasn't hooked up to an apex controller, It would of destroyed the tank. I've tried all the jumper settings, and nothing seems to make a difference.
I've been fighting this for 6 weeks now, I'll be switching back this weekend.
Pump is the weak link By Marc on 1/17/14Marc wouldn't recommend this product to a friendIt'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 1/9/14Scott would recommend this product to a friendAfter 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 1/6/14Jared would recommend this product to a friendAt 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 12/28/13trent would recommend this product to a friendno 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 12/19/13Easiest install ever would recommend this product to a friendI 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 12/16/13Michael would recommend this product to a friendEasy 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.
Ask a Question About 'Tunze Osmolator Universal 3155 Auto Top Off'
Previously Asked Questions
by BILL on November 13, 2013, @7:37 AM
what pump do you suggest to go with the3155 osmolator?
Bulk Reef Supply Hey Bill,
The Osmolator actually comes with the pump right in the package so you don't need to buy one!
by Jeff on November 28, 2013, @2:50 PM
How much head will the pump push
Bulk Reef Supply Hey Jeff,
The pump on the osmolator has a max head height of 7ft.
by Ronald on January 13, 2014, @2:32 AM
Just wondering if I need 2 ATO. I know you can place it either in the sump or in the tank, but my question is if I place it in the sump will it also refill my tank in that process. I don't see that happening but if it does please let me know.
Bulk Reef Supply Hi Ronald,
If you have a sump, it MUST go in the sump, in the chamber where your return pump is. This is the only area of your tank that will have a changing water level depending on evaporation (unless its far too late!). Only one ATO would be necessary but it must go in that location if you have a sump.
by Daire Fontaine on January 17, 2014, @12:23 AM
My Tunze Osmolator ATO keeps getting stuck in the ON position. I soaked the electronic eye in vinegar and it was fine for a week, but then it stuck on again. Do these electronic eyes fail after many years of use? I've been using it for about 4 years. Is there any way to replace the eye without having to buy a whole new system?
Bulk Reef Supply Hi Daire,
We run into very few issues with these but after that length of time I would imagine its possible for any component to fail. We don't have individual parts like the optical eye, but if you give Roger and company a shout over at Tunze USA, he might. At the very least he could likely help you narrow down exactly what it is. The number I have for them is 512-833-7546 email@example.com
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