Let's talk ATOs

solitude127

Proud user of IO Salt!
Let's talk ATOs.
In my eyes, if you have a Reef Tank, an ATO is a must. Some people have gotten away with filling it manually but knowing myself, I probably would always forget and have salinity swings. I know there are a ton of ATOs systems out there and there a few that are really popular like Tunze for example. Here are a few that I've used.

- Avast Marine (currently using in DT)
- Tunze (full version)
-Tunze Nano
- JBJ (currently using in my Red Sea 170)
- Reef Fanatic
- XP Aqua Duetto (currently using in my QT)
- Gravity Fill with float valve (currently using in conjunction with my JBJ on my RS 170)

Let's talk a little about each
Tunze 3155
Probably the most popular and recommended that I've seen. It has an electronic eye to control the water level as well as a mechanical float switch as a backup just in case the water level rises too high. Not going to talk too much about this because it's been around a while I'm sure a ton of people are using them
Pump: DC pump provided by Tuzne
Pros: Tried and trued. Optical sensor. Backup Float Switch. Pump fits in a 5g jug
Cons: Cannot be integrated with a controller besides on/off
Tunze-Osmolator-Universal-3155-Auto-Top-Off-ATO-99.jpg


Tunze Nano 3152
This is the little brother of the 3155. This ATO is more of basic ATO with only a mechanical float switch to trigger the pump. It does have a nice feature of a float guard to keep critters out of the area where the float switch is. Until recently, I was using this on my QT tank and come to find out, it has a nice little protection feature against overflows. If you tank is over a certain amount of gallons, you can adjust the ATO (via jumpers within unit) to fill a little longer.
Pump: DC pump provided by Tuzne
Pros: Price is relatively inexpensive. Uses the same pump as its big brother. Programming to shut off if pump is running to long. Pump fits in a 5g jug
Cons: Has a mechanical float switch to trigger pump
Tunze-Osmolator-Nano-3152-Auto-Top-Off-ATO-99.jpg


JBJ and ReefFanatic
I'm going to group these 2 together because they have very similar features as I've used both. Both use mechanical float switches and both have programming switches to determine what each float switch does.
Pump: an open outlet on the controller is provided to use a pump of your choice.
Pros: Dual floats included to do multiple things
Cons: no pump

JBJ-ATO-Automatic-Top-Off-System-Water-Level-Controller-99.jpg

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XP Aqua
I'm currently using this one on my QT and really like it so far. There are dual electronic water level sensor. The "œbrain" of the unit is compact just like the sensors. This unit also come with a DC pump. What I like about the pump is that it'll fit in the neck of a 5g jugs most of us use.
Pump: DC pump provided by XP Aqua
Pros: Compact unit. Pump fits in a 5g jug. Programming if pump runs too long
Cons: New to the market

XP-Aqua-Duetto-Dual-Sensor-Complete-Aquarium-Auto-Top-Off-ATO-System-99.jpg


Avast Marine ATO
I'm currently using this on my DT and really like this one. There are many options to run this pump, there is a stand alone controller and can be attached to some sort of controller (APEX, ReefAngel, etc). What I really like about this pump is that the mechanism to fill the tank is a pressure switch. Unlike the previous ATO's mention, there nothing to clog up mechanical float switch nor an electronic eye to keep clean.
Pump: an open outlet on the controller is provided to use a pump of your choice or can be hooked up to your controller to activate an outlet.
Pros: Can be integrated with controller. Pressure switch to activate pump. Backup float switch
Cons: No pump

LG-ato_1024x1024.jpeg




What do you guys use?
Also, please feel free to add to the list.
 
I just top off the tank every 2 days

Reef tank stability is very important for long term success in the hobby. By topping off every couple of days, you are subjecting your livestock to wild swings in salinity.
 
Call me cheap, but I've bought this for 2 separate aquariums, and it works great. Never had an issue. One has been working for 5 years. I get the one that says, "double with bracket".

http://autotopoff.com/Standard/index.html

I use this dosing pump for my pump. I like it because it's again..cheap, lol. But also it pumps very slowly so it doesn't affect your salinity too much if you slack a little, unplug your ato and wait for your new rodi water to be made. Lol.

https://www.chewy.com/tom-pet-produ...MI2IeQtfz-3QIVC1YNCh0HOgbjEAQYASABEgLlsfD_BwE

Sent from my SM-G935T using Tapatalk
 
Unfortunately, I've never used SpectraPure ATO but I've heard nothing but good things

Mike just for clarification...
The Litermeter III is touted as a dosing pump that can perform as an ATO vs calling it an ATO per say.
The APEX DOS is basically the same, a dosing pump the can perform as an ATO, AWC, Dosing.
So not to confuse, APEX also sells an ATO that has optical sensors, a safety float valve, pump and FMM (Fluid Monitoring Module). This will work stand alone, or integrate with an Apex controller. The DOS will not work stand alone, you need an Apex to control it.
 
Not the 1st but the second is now in use.
+ they can be repaired if necessary.
The newer one was an upgrade for something or other, don't remember, + it was used when I bought it. I did have to replace the motor when it went online.
 
I've been at it for 30 years now. I've never used an ATO because I've had too many things fail on me to trust one fully.

FWIW - my 120g DT is SPS dominated slightly mixed reef. IMHO/IME, the few gallons that evaporate over the course of 2-3 days isn't that big of a swing to really harm anything. I do have my topoff water plumbed up to the back of the tank and controlled by a remote switch so that I don't have to schlepp buckets anymore.
 
I use food grade liquid level switches, a small 12VDC powered solenoid, and a Brute for my DIY gravity fed ATO. It's bulletproof and has been operating for years without fail. It also keeps the level within about 1/2". All I have to do is fill the Brute every 3-4 weeks.

3 switches are wired in series to control power to a normally closed solenoid: 1) a normal level switch closes when the level drops below the desired sump level and opens when the level returns to normal; 2) a high level cut off opens when the level rises too high; and 3) a low level switch opens when the level falls too low to protect the solenoid from over heating. Finally, a Kent mechanical float valve is installed as a final fail-safe. It will cut-off flow if the sump get just slightly higher than the high level switch level.

The switches are about $12 each, the solenoid is about $20, any little 12 volt power supply will run the thing. You probably have one laying around the house or can buy one a Radio Shack for a few bucks. The load is very small, but make sure all the components are rated accordingly.
 
Mike just for clarification...
The Litermeter III is touted as a dosing pump that can perform as an ATO vs calling it an ATO per say.
The APEX DOS is basically the same, a dosing pump the can perform as an ATO, AWC, Dosing.
So not to confuse, APEX also sells an ATO that has optical sensors, a safety float valve, pump and FMM (Fluid Monitoring Module). This will work stand alone, or integrate with an Apex controller. The DOS will not work stand alone, you need an Apex to control it.

Thank you for the clarification. I've always loved spectrapure pump and when I heard that they might come out with a continuous duty peristaltic pump for CaRx, I got excited but I don't think anything ever materialized.


I've been at it for 30 years now. I've never used an ATO because I've had too many things fail on me to trust one fully.

FWIW - my 120g DT is SPS dominated slightly mixed reef. IMHO/IME, the few gallons that evaporate over the course of 2-3 days isn't that big of a swing to really harm anything. I do have my topoff water plumbed up to the back of the tank and controlled by a remote switch so that I don't have to schlepp buckets anymore.

If it ain't broke, why fix it. :)

I use food grade liquid level switches, a small 12VDC powered solenoid, and a Brute for my DIY gravity fed ATO. It's bulletproof and has been operating for years without fail. It also keeps the level within about 1/2". All I have to do is fill the Brute every 3-4 weeks.

3 switches are wired in series to control power to a normally closed solenoid: 1) a normal level switch closes when the level drops below the desired sump level and opens when the level returns to normal; 2) a high level cut off opens when the level rises too high; and 3) a low level switch opens when the level falls too low to protect the solenoid from over heating. Finally, a Kent mechanical float valve is installed as a final fail-safe. It will cut-off flow if the sump get just slightly higher than the high level switch level.

The switches are about $12 each, the solenoid is about $20, any little 12 volt power supply will run the thing. You probably have one laying around the house or can buy one a Radio Shack for a few bucks. The load is very small, but make sure all the components are rated accordingly.

Sounds like a viable option. I wish I was more mechanically inclined. :)
 
I run 2 of the JBJ units and except for cleaning the floats once in a while they have been flawless. I use a single float on a 24 gal nano tank and both floats under my 180. The one I have under the 180 I had to open up and change the run time on it so it would't time out.
 
I'm a new guy and can't imagine how you could be in this hobby WITHOUT an ATO!!! I personally use the Innovative Marine ATO https://www.amazon.com/Innovative-Marine-Hydro-Fill-Controller/dp/B016FLD2A2
I like it because you can use any pump you want. I have a little Rio 600 pump and a 7.5gal Rubbermaid storage container. I just have to fill up the ATO with RODI 1x/wk and I'm good to go. In July, my tank would evaporate a little over a gallon a day, so I couldn't imagine trying to refill the tank every day. ATO for sure!
 
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Is there anything wrong with just running a line from my RO/DI unit to a float valve in my sump? As long as I have water pressure (which is 99.999% of the time) I can keep the level constant. I've been doing this since I installed this tank in 2000. Never had a problem.
 
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