Great Product! By Andy on 6/8/13

Andy would recommend this product to a friend

I purchased this item about a year ago for my Red Sea Max 250. The skimmer on that tank is very finicky and needs constant adjustments to work properly when the water level changes. This ATO has fixed that issue for good! I have a five gallon bucket of RODI water sitting under the tank for top off purposes and the Osmolator takes care of the rest. My tank water level is always where it needs to be and my skimmer is running at optimum efficiency. If you're looking for a good quality and reliable ATO look no further!

Working great for the past 8 months By Ron on 6/3/13

Ron would recommend this product to a friend

Have had this ATO unit for almost 8 months on a 90 Gal reef with no issues. Working as good today as the day I got it. Set up was easy. No more having to add top off water every day.

Excellent Product, Well Worth the extra $$$ By Huck on 6/1/13

Huck would recommend this product to a friend

Initially, I was reluctant to spend the extra money on the Tunze. I did tons of research and I saw this product had excellent reviews, but what sealed the deal for me is, I was reading reviews on a JBJ auto top off system and someone who purchase a JBJ stated that he wish he would have went with the Tunze and not taken the cheaper option.
Unit has been in service now for approx 3 months and not a single problem. Definitely the way to go!

Top-notch !!!!!!!!! By Jimbo on 5/30/13

Jimbo would recommend this product to a friend

Sweet, could't ask for a better quality ATO system.Like the redundency with the Sensor and the float switch combined.
Excellent product. Worth the extra investment.

Works great when it is working, if you can figure it out By tramboneplayer5 on 5/18/13

tramboneplayer5 would recommend this product to a friend

The instructions for this are terrible. For something that costs this much, I think they could have hired a better translator to write the instruction manual. After watching people on youtube and reading threads on reefcentral, I am pretty sure I have it all together, but the water line occasionally falls out of the pump and the pump will continue to run while shooting water up in the air. Be sure to have a lid on your water reservoir.

For $200, I don't get a finished product? By Mike on 5/15/13

Mike would recommend this product to a friend

I haven’t set it up yet and I’m sure it will work as advertised, but it contains a feature that is a pet peeve so excuse me while I rant a bit. The pump connects to the controller via two bare metal wires that have to be manually wired to a “terminal” connected to the controller. The manual does not explain how this is to be done. I got instructions from Tunze and had the strong impression that the rep thought I was either lazy or stupid for asking. I may be both, but when I pay more than $200 for an electrical product, I expect it to be fully wired. What would it have cost Tunze to add two snap in parts to connect the pump and the controller? A few pennies extra for each piece? So why didn’t they do it? I suspect because Tunze, like other major manufacturers of aquarium equipment, assumes that they can cut corners and the customers won’t complain. Well, it’s really no big deal, right? But what if you bought a top of the line coffee maker for $200 and it required that you wire the plug to make it work? Would that be ok? How about the numerous Chinese manufacturers who provide instructions for their product in absolutely incomprehensible English? I could go on. But if this kind of thing occurred in any other consumer market, there be an outroar. But since it’s just an aquarium product, we just shrug and look for a work around. IMO, we deserve better

good for a while By lwillis22 on 5/15/13

lwillis22 wouldn't recommend this product to a friend

I have had this product running on my 125 gallon tank and it has been a life saver. However, it started malfunctioning and I had to return it to Germany to get fixed or replaced. It cost me $35 to ship it there and that was the cheap route. It has been 1 1/2 months since I shipped it out and still no contact from them.

What a Great Product: By Bruce on 5/9/13

Bruce would recommend this product to a friend

For anyone that wants peace of Mind about their aquarium, this is the product for you. An accurate, automatic device that will add DI water or Kalkwasser to your Sump is the way I use it. Perfect for the person that makes short trips, without the worry of evaporation causing your salinity levels to rise while your gone. A perfect 5 from Me.

A MUST for larger tanks with large evaporation rates! By RandoReefer on 5/7/13

RandoReefer would recommend this product to a friend

After upgrading to a 125g tank with a 30g sump, I noticed my evaporation rate upgraded also. One week of manually topping off 1.5gal per DAY, was enough for me to pull the trigger on this ATO.

I really trust the sensor on this system! I was close to buying the JBJ Auto Top Off but I'm so glad I put up the extra money for this one. It is sleek, provides a variety of setup options, VERY Accurate, and easy to setup. I gave it 4.5 stars, because it could have used a few more directions or a FAQ section.

Why didnt i get one sooner! By Jason on 5/1/13

Jason would recommend this product to a friend

I finally made this purchase and its a life saver!
comes with everything needed (except water container).only issue is the
eye sensor gets micro bubbles on it when first installed which causes it to pump water continiuosly till high level alarm shuts it off.best advice is clean sensor with vinegar and let it sit in your sump for a couple days then its trouble free.

The best hands down. By Alex on 4/13/13

Alex would recommend this product to a friend

Tunze osmolator top off is the best system you can buy. Well worth the price, comes with its own pump and has 2 different technologies working flawlessly to protect your tank and home from a flood.

great ATO By illya on 4/13/13

illya would recommend this product to a friend

This is my second unit i'm ordering, first one was about 2 years ago. This is for a second setup, the first one is doing great. The one problem with these is the power plug. After sometime it becomes corroded and you get strange errors like overfill alarm wont stop. But if you have any problem the first thing to do is take off the 2 screws and clean the port and the plug. I cut a nail file down to about 1/8" to clean the port, and just a drill bit to scrape the plug inside. worked great and im good for another 6 months at least. At some point i'll just solder the wires and never deal with it again.

Worth every penny!!! By Steven on 4/5/13

Steven would recommend this product to a friend

You do get what you pay for... Keeps my water level constant. Love the optical sensor they use on this system. No brainier to install. Now all I need is to make something to hide the top off container...

awesome product By brian on 4/4/13

brian would recommend this product to a friend

I recently upgraded my 60 gallon reef tank to a 180 gallon. With my 60 I just topped off the old fashioned way but that was getting to be a chore with the new tank. I was on board with purchasing an auto top off but had serious concerns about failure...particularly in the on position. Virtually every other ato product out there was peppered with negative reviews regarding failure. We have thousands invested in the tank so it was worth it to spring for the osmolator. Piece of mind and very easy to setup. Skimmer works a lot better to.

Amazing By Dan on 3/27/13

Dan would recommend this product to a friend

Probably one of the best investments I have made in this hobby. A really solid product.

Excellent product By P Duffles on 3/25/13

P Duffles would recommend this product to a friend

I'll simply agree with the multitude of people praising this ATO. This thing literally changed my life :D

The best By FISHY on 3/25/13

FISHY would recommend this product to a friend

The best thing that you can do to your tank.

Good Top Off Bad Instructions By Mike on 3/25/13

Mike would recommend this product to a friend

The instructions on this top off could be WAY easier to understand if it didn't have 6 different languages on each page. Also, it should also state in there that you need to soak the opitcal sensor in soapy water and gently wipe off the polishing residue on the sensor before installation, also there is a dial on the inside of the controller that you need to set depending on the size of the aquarium or sump that you place the sensor in, the dial basically sets the dosing the pump pumps water into the tank/sump. A little better instructioni pamphlet would give this product 5 stars!

Great product!! By Bosley on 3/15/13

Bosley would recommend this product to a friend

I have this running on my aquarium and it is spot on and fail proof . the back up plunger has not been activated Probably because the top off system works so efficient, Great product recommend to anyone who is tired of adjusting or just having other systems that fail.

Not Cheap..you get what you pay for By Curtis on 3/10/13

Curtis would recommend this product to a friend

Best ATO available

Love It!!! By Troy on 3/2/13

Troy would recommend this product to a friend

You get what you pay for, and this ATO is awesome!!! Easy to setup and fail safe. Great quality.

Serious about reefing? Get this! By Chris on 2/28/13

Chris would recommend this product to a friend

One of the smartest purchases I've made. Expensive but made with quality and plenty of mounting options. Highly recommend!

Worth the Investment By JOHN on 2/24/13

JOHN would recommend this product to a friend

I was a little apprehensive about spending this kind of money on an ATO. From the moment I opened the box I recognized the quality. Works perfect, provides piece of mind, and everything you need is included. Previously bought JBJ but was disappointed due to lack of redundancy. This should be fail proof with dual sensor/float valve.

Tunze ATO By Toby Flenderson on 2/23/13

Toby Flenderson would recommend this product to a friend

Pros: works perfectly, precisely, the German way.
Cons: hard to fight off all the ladies who want to get there hands on my tunze.