Are any ATOs really safe?

[Schmidt Aquatics]

I think ATOs are a pretty interesting topic, mainly because of the potential risk of flooding your floors from a faulty ATO overfilling your tank.

ATO devices just seem to always bear that risk. Firstly, you will have multiple points of failure. I know many praise the Tunze ATOs, but even here you will still hear a few stories of overfilling the tank.
Many ATOs include a chip-based failsafe, where if the device is turns on the pump for more than a given time frame, it will automatically stop the pump. Or, alternatively, it can detect if a sensor seems faulty. But if any of you work in tech, you also know how often chips can fail (especially the cheap ones used for aquarium equipment). So, single point of failure right there.

I do hear of mechanical ATOs, often gravity fed, which does make a lot of sense, but isnt always an option for those with small AIO tanks, where you dont have enough space for a high quality float valve, as they are quite bulky.

So, are ATOs ever REALLY safe, or is it just a major risk we will always have to take as saltwater hobbyists?
Are there any redundancies or failsafes you can implement to reduce or eliminate the risk entirely?

 

[Stephen8169301]

Following

 

[JoJosReef]

I think ATOs are a pretty interesting topic, mainly because the potential risk of flooding your floors from a faulty ATO overfilling your tank.

ATO devices just seem to always bear that risk. Firstly, you will have multiple points of failure. I know many praise the Tunze ATOs, but even here you will still hear a few stories of overfilling the tank.
Many ATOs include a chip-based failsafe, where if the device is turns on the pump for more than a given time frame, it will automatically stop the pump. Or, alternatively, it can detect if a sensor seems faulty. But if any of you work in tech, you also know how often chips can fail (especially the cheap ones used for aquarium equipment). So, single point of failure right there.

I do hear of mechanical ATOs, often gravity fed, which does make a lot of sense, but isnt always an option for those with small AIO tanks, where you dont have enough space for a high quality float valve, as they are quite bulky.

So, are ATOs ever REALLY safe, or is it just a major risk we will always have to take as saltwater hobbyists?
Are there any redundancies or failsafes you can implement to reduce or eliminate the risk entirely?

Good question.

I am running the IM TI Hydrofill on my new IM Nuvo 40L AIO. Previous ATOs were all bottles on top of nano tanks, which even if there were a failure (maybe a leak in the cap? puncture in the tube allowing oxygen in?) it would not cause a flood.

Now, with this ATO on the 40 gal tank, which is in an office, I worry about the ATO triggering and not stopping. So, currently looking into adding one of the AutoAqua water level safety switches. If it detects the water level rising past the optical sensor, it should cut the power to the ATO, which will stop the pump.

Now, where is the fail safe if the AutoAqua switch fails and (A) doesn't cut off the power to the ATO, or (B) cuts off the power to the ATO when there is no overfilling, thus causing unabated evaporation (imagine this happening over a weekend)?

Seems like there's almost no way to be 100% safe when you get to the bigger tanks.

 

[Schmidt Aquatics]

Good question.

I am running the IM TI Hydrofill on my new IM Nuvo 40L AIO. Previous ATOs were all bottles on top of nano tanks, which even if there were a failure (maybe a leak in the cap? puncture in the tube allowing oxygen in?) it would not cause a flood.

Now, with this ATO on the 40 gal tank, which is in an office, I worry about the ATO triggering and not stopping. So, currently looking into adding one of the AutoAqua water level safety switches. If it detects the water level rising past the optical sensor, it should cut the power to the ATO, which will stop the pump.

Now, where is the fail safe if the AutoAqua switch fails and (A) doesn't cut off the power to the ATO, or (B) cuts off the power to the ATO when there is no overfilling, thus causing unabated evaporation (imagine this happening over a weekend)?

Seems like there's almost no way to be 100% safe when you get to the bigger tanks.

I’ve thought of doing the same (adding the AutoAqua sensor for added redundancy), but you’re absolutely right, that can definitely fail too.

I only keep a container with enough RO water for a week worth of evaporation. But I also never went away for more than a week. However, evaporation can change a lot depending on room temperature and humidity, so that can be hard to calculate. Also, a week worth of RO would still flood my tank in case of ATO failure, just not as much.

 

[C_AWOL]

In the case of utilizing the hydros controllers ato, you can set a max run time. If it exceeds that then it will shut off for a set time and you will get a notification. You can also do an additional manual override off to ensure it wont continue pumping at any point and time there after and even add a physical float valve (if able) that the pump can't possibly over power.

 

[JoJosReef]

I’ve thought of doing the same (adding the AutoAqua sensor for added redundancy), but you’re absolutely right, that can definitely fail too.

I only keep a container with enough RO water for a week worth of evaporation. But I also never went away for more than a week. However, evaporation can change a lot depending on room temperature and humidity, so that can be hard to calculate. Also, a week worth of RO would still flood my tank in case of ATO failure, just not as much.

So my final fail safe is mechanical. If the tank overflows, the overflow gets caught in a galvanized steel pan placed under the stand (also nice for providing level surface on office carpet):

The dimensions of that pan can hold 4 gallons of water. Remove the space taken by the stand frame (hollow between), and I would guess it can comfortably hold 3 gallons before spilling onto the carpet.

With a 5 gallon ATO jug in the stand, I think it can overflow the tank, but probably not by >2-3 gallons. So, worst case in terms of office mess would be having to drain the pan (siphon or towels). Worse for the tank inhabitants, of course. Corals/fish might not like the diluted saltwater, but still might not be too bad. Urchin would die for sure, as well as anything else sensitive to salinity swings.

 

[Schmidt Aquatics]

In the case of utilizing the hydros controllers ato, you can set a max run time. If it exceeds that then it will shut off for a set time and you will get a notification. You can also do an additional manual override off to ensure it wont continue pumping at any point and time there after and even add a physical float valve (if able) that the pump can't possibly over power.

The max run time can fail, as that is done through a chip. Chips fail too.

Float valves are very good, I think anyone who has room for one, and who can add it to their ATO setup should do so. They are cheap, you just need to know which ones are highly quality. There are some good ones used for toilets. Even if it is stuck, it will only be able to remain in “off” and not “on” and thereby flood the tank.

 

[Schmidt Aquatics]

So my final fail safe is mechanical. If the tank overflows, the overflow gets caught in a galvanized steel pan placed under the stand (also nice for providing level surface on office carpet):
View attachment 3104407

View attachment 3104408

The dimensions of that pan can hold 4 gallons of water. Remove the space taken by the stand frame (hollow between), and I would guess it can comfortably hold 3 gallons before spilling onto the carpet.

With a 5 gallon ATO jug in the stand, I think it can overflow the tank, but probably not by >2-3 gallons. So, worst case in terms of office mess would be having to drain the pan (siphon or towels). Worse for the tank inhabitants, of course. Corals/fish might not like the diluted saltwater, but still might not be too bad. Urchin would die for sure, as well as anything else sensitive to salinity swings.

That definitely will do its justice, yes. For bigger tanks which evaporate even more, I guess we would have to dig a moat around the tank!

 

[vtecintegra]

I consider my Tunze safe, but I still use a high level sensor with the Apex to shut it off if it overflows, and a water on the floor sensor that would shut it off as the next safe guard..

 

[C_AWOL]

The max run time can fail, as that is done through a chip. Chips fail too.

Float valves are very good, I think anyone who has room for one, and who can add it to their ATO setup should do so. They are cheap, you just need to know which ones are highly quality. There are some good ones used for toilets. Even if it is stuck, it will only be able to remain in “off” and not “on” and thereby flood the tank.

Fortunately you can add a high water level sensor if desired for yet another form of redundancy in my example

Low water sensor (notification+pump on)) + max run time (notification+pump off for X time) > manual overide off (if desired) + float valve (absolute max fill level unless pump unlikely over powers it/is a non fixed model) + high water sensor (better check on tank because all hell probably broke loose + pump off) + leak detector rope/puck (pray to whatever god/diety/flying spaghetti monster that your significant other/landlord/relatives/friends/other pets? forgive you) would set you up to be pretty darn safe other than if the controller plain out fails/power goes out (which would take out the ato anyways in this case)

 

[Pistondog]

I think ATOs are a pretty interesting topic, mainly because of the potential risk of flooding your floors from a faulty ATO overfilling your tank.

ATO devices just seem to always bear that risk. Firstly, you will have multiple points of failure. I know many praise the Tunze ATOs, but even here you will still hear a few stories of overfilling the tank.
Many ATOs include a chip-based failsafe, where if the device is turns on the pump for more than a given time frame, it will automatically stop the pump. Or, alternatively, it can detect if a sensor seems faulty. But if any of you work in tech, you also know how often chips can fail (especially the cheap ones used for aquarium equipment). So, single point of failure right there.

I do hear of mechanical ATOs, often gravity fed, which does make a lot of sense, but isnt always an option for those with small AIO tanks, where you dont have enough space for a high quality float valve, as they are quite bulky.

So, are ATOs ever REALLY safe, or is it just a major risk we will always have to take as saltwater hobbyists?
Are there any redundancies or failsafes you can implement to reduce or eliminate the risk entirely?

We work in 'tech' and chips dont fail that often if heatsunk and applied correcly.
I have not heard of tunzes failing on, have you?
The main problem ive had with tunze is the prism sensor. It requires cleaning maybe once a year, and after cleaning, you need to wait a couple of days for the biofilm to grow back to repel microbubbles.

 

[JoJosReef]

We work in 'tech' and chips dont fail that often if heatsunk and applied correcly.
I have not heard of tunzes failing on, have you?
The main problem ive had with tunze is the prism sensor. It requires cleaning maybe once a year, and after cleaning, you need to wait a couple of days for the biofilm to grow back to repel microbubbles.

One of the reasons I decided to try the titanium sensors. I don't know what might cause them to fail, though.

 

[JCM]

I've been using the JBJ ATO's for years, never a problem.

That said, my main failsafe is my sump can hold my entire top off container without overflowing. Top off container is 5 gallons which lasts about a week. It would probably drop salinity enough to make my coral angry but my floors are safe.

 

[((FORDTECH))]

So I use an apex and due to that have 2 fail safes. First one is I have high water level optical sensor that if triggered does 2 things first will shut off ato and second will send my cell phone text message alarm of the event. Second is I have figured out that anytime I need a top off the pump does not need to run longer then 30 seconds so I set a program that if the ato runs more then 30 seconds it also will shut ato off and also send cell phone text message alarm. This is brainless and will never fail with the Redundant apex failsafes

 

[Dine]

Is holding back x amount of water in your home with a bead of silicon really that safe? ATOs have their risks, paly toxin is a risk, lots of risks in this hobby. All we can do is hope for the best and prepare for the worst. Redundant fail safes, maintenance, and a bit of luck is what keeps these things flowing

 

[c0kefree]

I have trust issues with mechanical and electrical “fail safes” around things that i put my blood, sweat, and tears into.

I use my Reefer’s glass ato which only holds about 1 1/2 gallons that is fed by an aquaduetto ato from a 5 gallon reservoir in a cabinet near by. I use the Neptune LLS’ to monitor both my ato’s volumes and i manually add more via my apex (by turning on the aquaduetto) based on that.

it can never dump more than a gallon in at a time, which doesn’t do much to the salinity.

 

[doubleshot00]

I consider my Tunze safe, but I still use a high level sensor with the Apex to shut it off if it overflows, and a water on the floor sensor that would shut it off as the next safe guard..

I do this exact method. I use a LLS though.

I just can’t imagine not using a Tunze ato now that i have one.

 

[GarrettT]

Big sump, small reservoir, no problem.

 

[merkmerk73]

Once you've added several redundancies you've done about all you can

 

[Not woodyarmadillo]

Just wanted to chime in. I have the Tunze nano and I’ve caught it going into a vacuum a couple times. The first time I was working on the tank and I turned the pump off. I heard water running and looked at my ATO reservoir. The line had somehow created a vacuum and it was pulling tank water into my ATO reservoir. It filled up and I probably got about a gallon on the floor. Had to clean it up, add tank water and refill ATO container. I try to keep the line above the water line even when the pump is off now but I did briefly catch it doing it again once. Luckily this would normally only happen when I’m working on it and have pumps off but it’s definitely a possibility and something to watch out for. Could be bad if you’ve got a large tank.