Gravity ATO vs E lectronic

[Swingline77]

Pardon the post if this has been discussed elsewhere. I did a quick search, and didn't come up with comparisons. It's clear from my reading that both gravity ATOs and Electronic ATOs work well. There are differences in that with those that are gravity fed, failure seems less likely, given this design's simpler nature. However, it seems that a gravity fed ATO failure would be far more catastrophic than an electric ATO failure, assuming a failsafe timer is used with an electronic ATO. The gravity fed ATO can work with a power outage, but I don't see this as an issue, since an outage would affect more than just the ATO. So, an electronic ATOs failure in the event of an outage can be addressed as the needs of the other electronic devices are addressed with a generator, etc.

So, all in all, what do you think is the better option, ignoring cost?

 

[MichaelReefer]

Pardon the post if this has been discussed elsewhere. I did a quick search, and didn't come up with comparisons. It's clear from my reading that both gravity ATOs and Electronic ATOs work well. There are differences in that with those that are gravity fed, failure seems less likely, given this design's simpler nature. However, it seems that a gravity fed ATO failure would be far more catastrophic than an electric ATO failure, assuming a failsafe timer is used with an electronic ATO. The gravity fed ATO can work with a power outage, but I don't see this as an issue, since an outage would affect more than just the ATO. So, an electronic ATOs failure in the event of an outage can be addressed as the needs of the other electronic devices are addressed with a generator, etc.

So, all in all, what do you think is the better option, ignoring cost?

I would say Gravity. More technology = more chance of a problem.

 

[Midrats]

I like the gravity fed ATO on my Reefer. I have an Osmolator and a Litermeter, and prefer the stock ATO. People complain that the reservoir only holds three days worth of evaporation, but that is the whole point, the whole reservoir could drain into my sump and it wouldn't overflow, or disturb the inhabitants too much. Tunze recommends small reservoirs for the same reason.

 

[Swingline77]

I like the gravity fed ATO on my Reefer. I have an Osmolator and a Litermeter, and prefer the stock ATO. People complain that the reservoir only holds three days worth of evaporation, but that is the whole point, the whole reservoir could drain into my sump and it wouldn't overflow, or disturb the inhabitants too much. Tunze recommends small reservoirs for the same reason.

Out of curiosity, what is the volume of your system, and how much evap do you get per day?

 

[S2G]

Your float valve will clog really easy with gravity. Ask me how I know lol

 

[biecacka]

How does ones float valve clog easily with gravity but not with an electronic ATO. I’m not denying your statement, just asking why there is a difference.

corey

 

[MichaelReefer]

Your float valve will clog really easy with gravity. Ask me how I know lol

Thats why you Maintenance it.

 

[Swingline77]

Aren't there gravity ATOs that don't use switches, and instead use two tubes?

 

[Midrats]

I just take a pipette and stick the tip into the outlet inside the reservoir and blast water out forcefully through the float valve. I do this occasionally, maybe once or twice a month and it keeps it flowing.

 

[Gw2kpro]

Aren't there gravity ATOs that don't use switches, and instead use two tubes?

Yes. And there are some that use one tube. Like this one:

DIY Gravity ATO - How?

Hi! So, I’ve saw a post in here about using gravity as a ATO. I’m thinking of using a bottle such as a smart water bottle. If I understand how it works correctly the bottle needs to be higher than the tank. I’d put fresh water in the bottle and then insert a tiny air tube/water tube into...

www.reef2reef.com

That post inspired me to build a larger one out of a 1.5 gallon carboy style bottle I had (mine has a spout/ hand valve at the bottom and can be filled from the top).

I run the tube from the spout at the bottom into the return pump section of my sump, which will drop level as my system evaporates. As soon as the level inches below the tube, air enters the tube and water drains slowly into the sump. Once the water level in the sump covers the tube opening again air stops going into it and it stops draining.

Works like a champ.

Nothing mechanical to fail. Just important to make sure everything is airtight.

 

[RichReef]

I use a 5 gallon Eshopps reservoir and an Eshopps float valve. I do not dose through my ATO so it's not likely to clog. I would be surprised if it ever had a problem. 8 years running. No maintenance.