Kessil

Best ATO

I'm in the market for a new sump, and finally (don't laugh) for the first time going to have an ATO set up. Is there a good/better/best ranking of different ATO switch systems? Float vs optical vs ??? I don't have any patience for 'fiddly' gear that requires frequent maint/tweaking to work properly. I've got an apex on the way if that makes a difference.
 
In the 4-ish years I've been playing with reef tanks, I've tried 4 kinds: Neptune ATK, the Autoaqua "smart" ATO, and the avast marine switch, hooked up to my Apex with a BRS 50ml/min pump.

Of those 3, the only one that has never given me a single problem, and that I have been running the longest, is the avast marine.

I did try hooking up a Tunze 3155 on my QT tank last night, and it was giving me problems so I unplugged it. Need to play with it a bit more to see if I can make it work for me. I'm optimistic because they do have such a good reputation.
 
The new aquasmart ATO’s added a light to the sensor, which vastly improved their performance in dark sump setups. I’ve been running one for a few years and the only problem I’ve had is that I forget to fill the reservoir and it inevitably runs out of water aroumd 2am and the alarm wakes me up.
 
I only started using an ATO when I set up classroom tanks. I had no idea how awesome things are with an ATO! Everything stays more stable. I have only used Tunze regular and nano ATOs. The only issue I had was in setting up one of the nanos on a 22g tank with a large surface area/footprint. When I figured out with the manual and talking to people that I had to turn around a little piece inside the controller it was fixed and all 4 Tunze ATOs have been problem free. Bonus - Tunze's American main guy has a forum on ReefCentral, so you can find tons of Q & A and get individual help, if needed. Solid customer service. Tunze products are not cheap, but I think well worth the price.
 
My current favorite is the Neptune one, but only because I'm an Apex user and with some caveats. Tunze is a close second, and possibly better for people that never plan to run an Apex. Full details as follows:

1) Tsunami AT1. Air pressure based on water level, so no float switches to clog up with a snail or optical eyes to cause issues. I used to like these until I realized that a crack or pinhole anywhere in the air hose as it gets old will result in a flood. Avoid.
2) JBJ - Lower cost, generally robust. I've had a few issues with these that I never figured out, but it went away when I replaced the ATO. Call this one a decent budget option.
3) Tunze Osmolator. I know several people with these, generally happy. None ran it more than a couple years for unrelated reasons so I don't have any long term reports. It does have a nice built in backup, so very low flood risk.
4) Tunze Osmolator Nano. I'm having an issue with one of these now. I suspect it's a bad float switch, but it may just be the auto shut-off kicking in due to running a nano ATO on too large a tank. I need to make a settings change next time I'm in the area (guessing the same jumper change MolaMola made). On the plus side also a very low flood risk.
5) AutoAqua Smart ATO (and newer versions). Super easy to set up, won't flood the place. I have had one minor issue, on a unit that was used when it entered my care: A magnet on one of the older ones cracked and had to be replaced due to in water rust (sump side). This was fairly cheap to get, and of course very easy to swap out. The unit did not stop working during this time.
5) Neptune ATO. Downside is that it takes more space due to the float valve, so it is not suited for a nano or smaller all in one. In that case I'd go with the Tunze. On the plus side, if you do have the space this is yet another level of safety for preventing floods.
As a free standing unit (no Apex) it's ok. There is one thing, you MUST use the anti-siphon adapter that comes with it, even if you don't need it for anti-siphon reasons. Without it the line tends to air lock and the pump will regularly fail to prime. Once installing that it has been totally trouble free for me. I know two other people running this unit and both had the same issue, so it's critical the anti-siphon fitting be installed.
Since setting it up on my Apex (which has let me add all sorts of other cool programming) I have had one issue: I had an optical sensor gunk up and read as if there was water in the tank as the sump ran low. While a float switch would not have this issue, it's worth noting that I had it in an almost stagnant area in a system with as surface scum issue, so I doubt others will have this issue. I could also avoid this by reprogramming it to fill to the top level sensor rather than the bottom one.
 
Tunze 3155 by far. I’ve used them exclusively over the past 10 years and probably dozen tanks.Wouldn’t look any other way.
 
In the 4-ish years I've been playing with reef tanks, I've tried 4 kinds: Neptune ATK, the Autoaqua "smart" ATO, and the avast marine switch, hooked up to my Apex with a BRS 50ml/min pump.

Of those 3, the only one that has never given me a single problem, and that I have been running the longest, is the avast marine.

I did try hooking up a Tunze 3155 on my QT tank last night, and it was giving me problems so I unplugged it. Need to play with it a bit more to see if I can make it work for me. I'm optimistic because they do have such a good reputation.

Not sure if this is your issue but you can adjust the flow rate for smaller tanks that require lower amounts of top off.
 
Wow, a lot of these systems are beasts - fully integrated with their own controllers and pumps. I was kinda hoping for a sensor-only solution that I can hook into the apex to control a peri pump. This won’t be connected to and endless water supply so the concern for flooding isn’t tooooo bad. Does something like this exist?
 
Wow, a lot of these systems are beasts - fully integrated with their own controllers and pumps. I was kinda hoping for a sensor-only solution that I can hook into the apex to control a peri pump. This won’t be connected to and endless water supply so the concern for flooding isn’t tooooo bad. Does something like this exist?

If you already have an Apex why not just get put on an FMM and optical level sensor, or wire a float switch in directly?
You can use that to work your peri pump, a small 1Link pump, or tiny needle wheel on an outlet.

All of these are self contained, you plug them in to the wall and go on your way, but that does entail a bit more inside their boxes.
 
Before the ATK came out I used a Toms Lifter pump, two float switches and a BoB on the Apex for ATO control and that was inexpensive to setup and worked for years. Had a few issues with the yellow lead float switches, but you get what you pay for.
 
Auto top off .com uses a two float switch setup that works well. Used to be $55, haven’t looked in awhile. Has a low level switch that keeps water level stable, and a high level switch that will turn off pump if lower level switch gets stuck on. Comes with a outlet you plug your pump into. Very easy and cheap. I like the auto aqua smart nano. The nano is way better than the original version.
 
Last edited:
I'm a fan of the hydor smart level controller.

Work on temperature variation, no moving parts to jam or optical sensors to clean. Even when it's encrusted by coraline algae, it still works.

My only complaint is that it isn't adjustable. If I stick my hole arm in the tank to reach something on the bottom, the high level alarm starts going off.
 
Auto top off .com seeks just a two float switch setup that works well. Used to be $55, haven’t looked in awhile. Has a low level switch that keeps water level stable, and a high level switch that will turn off pump if lower level switch gets stuck on. Comes with a outlet you plug your pump into. Very easy and cheap. I like the auto aqua smart nano. The nano is way better than the original version.

I'd go with this one if you are connecting a peri pump; I had the same Mike uses and really miss it.
 
A lot of people have problems with the Apex ATO. Tunze 3155 is by far the best and most reliable
I never had any problems with my atk. It has a siphon break which was handy for me since my ato reservoir was higher than my sump. I screwed up with the tunze and didn’t think about it and it flooded my sump.
 
1) Beware pressure switch ATOs! I loved them until I saw one that had a pinhole somewhere in the line. It turned on, added water until it pressure was built, leaked down the pressure, turned on again, etc. It isn’t a full on failure, so the usual “on for too long” safety didn’t catch it. Fortunately the ATO chamber ran dry around the time the flood started. I didn’t fully read the Avast page so they might have a clever software fix.
2) Doesn’t Neptune already sell a similarly priced Apex breakout board?
 
Back
Top