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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.
Tunze Osmolator Universal 3155 Auto Top Off By james on 3/26/14james 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. just make sure the place you put the water into the tank is higher then the container you store the water lol
Great ato system By Judith on 3/26/14Judith would recommend this product to a friendI chose this system because it contains everything needed to set up. The first day the pump would turn on and fill up until the alarm sounded. After unplugging and letting sit in the sump submerged in water overnight, I replugged it in and haven't had an issue since.
Don't be cheep, its the best! By ryan on 3/20/14ryan would recommend this product to a friendthis is a great item, i enjoy how it works over and over with no problems. i unwired the back up float switch wire on mine and added it to the breakout box on the apex so i can have email alerts and not have to hear the dam buzzer during a water change
Best ATO worth the money!! By Ryan on 3/20/14Ryan would recommend this product to a friendWorth every penny!! Super easy to install and setup. All the parts seem high quality. Well worth the extra money.
I'd give it 6 starts if I could By Dariush on 3/19/14Dariush would recommend this product to a friendAll I can say is WOW. This thing is great. Setup was about as easy as it gets (Reader's Digest version below):
1. Mount sensors on bracket
2. Mount bracket to tank
3. Mount controller to stand
4. Connect tubing to pump and tank/sump
5. Connect pump to controller.
On my 20 gallon nano reef, this thing keeps the water level dead on accurate, and the default pump setting works just fine, although it is adjustable via a variable pot inside the controller.
The pump makes a slight hum while it is running, but it is hardly noticeable, and since it isn't running all the time, odds are you will never hear it.
flawless By angelo on 3/17/14angelo would recommend this product to a friendworks perfectly since i got it over a year ago. never an issue
Ask a Question About 'Tunze Osmolator Universal 3155 Auto Top Off'
Previously Asked Questions
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 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 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
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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