Must Have By Jason on 4/23/14Jason would recommend this product to a friendI can't believe I ever went without this! It flat works, no questions asked. Easy setup, no brained operation. Well worth it.
Set it and forget it By Arrick on 4/23/14Arrick would recommend this product to a friendThis product works exactly as described is easy to set up and will easily be the most trusted piece of equipment you will have in your system.
Don't skip out on this! By Michael on 4/22/14Michael would recommend this product to a friendAfter having a 180g reef leak from a poor install and destroy 1100sf of my house I have learned that there are certain items that you do not skimp on to save money and a good return pump and ATO are one of them.
Not only will you have the piece of mind that your ATO will not flood and ruin your floors but your reef will be happier and your skimmer will work like never before!
This ATO is amazing and is well worth the price.
So far, so good By Anneke on 4/17/14Anneke would recommend this product to a friendThis was easy to set up and started working immediately. There was no break-in period.
Very good product By KEITH on 4/15/14KEITH would recommend this product to a friendTunze 3155 works as described shut off valves are the best
Optic sensor failed By Me on 4/15/14Me would recommend this product to a friendI just came home, and the water level was 2 inches low.
Optic sensor out of the water but nothing happens.
Worked fine for one year thats all.
a must By Nick on 4/14/14Nick would recommend this product to a friendIt works, its everything it is supposed to be! I love the dual level sensors and the pump is near silent. I think everyone understands they need an ATO. This is the best way to go.
Keep Tank Stable By Mitchel on 4/12/14Mitchel would recommend this product to a friendAnother great product from a great manufacturer that has been around forever. This ATO helps keep your salinity in check which helps for a better overall stable system. What else can you ask for out of a product.
Simply works perfectly By Eldog on 4/7/14Eldog would recommend this product to a friendOperating top off for 230 gallon reef tank with 75 gallon sump for three years now. It's truly a set it and forget it system, maintains perfect top off levels for optimum in-sump skimmer operation.
Fool Proof By Ryan on 4/6/14Ryan would recommend this product to a friendI'm a rookie when it comes to saltwater reefing, this unit is by far the best purchase I have made. Easy to use and definetly plug & play
The Best By Matt G on 4/1/14Matt G would recommend this product to a friendEasy to set up works the way it is supposed to work. I am very happy with it so far.
This thing is awesome. By Bill on 3/27/14Bill would recommend this product to a friendWe bought this thing for a new tank set up we are doing, but then decided to do a gravity fed replenishment tank instead, so we weren't going to use this... until the next night when the auto top off on our current system died. I pulled this one out of the box and set it up in about 20 minutes or less.. This thing is amazing.. Works perfectly right out of the box and is super easy to set up. While we are going with gravity fed on our new tank, I would recommend this to anyone that can't do gravity fed.
Ask a Question About 'Tunze Osmolator Universal 3155 Auto Top Off'
Previously Asked Questions
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 firstname.lastname@example.org
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 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!
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