ATO failing / siphoning?

[Nanolifeuk]

My nano ATO has failed on me twice today. I couldn’t figure out why. It has just sprung to mind that the return pipe hose was very close to the surface of the water.

I can only hypothesise but my theory is a snail may have budged the sensor up slightly, causing ATO to kick in and water level to rise equal then above the return hose. It was above the failstop on the optical sensor too.

My question is can this cause a siphon ? my ATO res is on the floor below the tank.

 

[Tathamet]

Is it the tunze osmolator nano?

if so I’ve never had a snail pull it from the top (which would turn it off) but have had one reach in from the bottom and pull it down before.

Make sure it’s not upside down. I remember that not being super clear when I first set mine up lol.

another thing I’ve found is the magnet is so strong that it seems to pull the float into the wall on 5mm glass. I’m not really sure how because it seems to be only plastic. I’ve had to wedge a 1/4” piece of plastic between the glass and magnet to reduce that pull and stop it from getting stuck.

 

[Tathamet]

Sorry I completely miss read that somehow.

yes I guess that could cause it to siphon for a bit until the hose hits air again. Though I think the pumps for atos usually have some sort of anti siphon built in.

 

[Tuan’s Reef]

You need a siphon break. one of these or make one yourself with a T .

 

[Uncle99]

Yes, it would syphon back.
Of course, should be above the water line.
Several times a snail triggered my ATO. I put a plastic “guard” below the sensor so a snail could not block sensors. I have a cap on the mechanical sensor.
Never had the ATO trigger once in 4 years now.
If if helps.
You can also add a “multi-timer” off Amazon which allows you ATO power to come on just for a minute per hour, or whatever rate you have.
So if the first sensor (which I thought was always optical) fails, the second (mechanical) saves, and if both fail, the timer shuts off the ATO.
Your system will come on at regular intervals, just understand that frequency to put in the timer.
Best $20 I’ve spent.

 

[bestfishes]

+1 on a siphon break to solve your issue. Check tubing for debris to be sure.

 

[Nanolifeuk]

You need a siphon break. one of these or make one yourself with a T .

Hi, I have a siphon break , it came with the ATO.

Several times a snail triggered my ATO. I put a plastic “guard” below the sensor so a snail could not block sensors. I have a cap on the mechanical sensor.

Sounds a good idea. It’s an AIO tank so I usually have no livestock in the back chamber where sensor is. I had a crab misbehaving so threw it in the sin bin for a while & this snail at the same time. Won’t be doing that again

I wasn’t aware you can siphon against gravity, but I suppose the mechanical aid of the ATO pump caused enough low pressure to do it ?

 

[Uncle99]

Hi, I have a siphon break , it came with the ATO.

Sounds a good idea. It’s an AIO tank so I usually have no livestock in the back chamber where sensor is. I had a crab misbehaving so threw it in the sin bin for a while & this snail at the same time. Won’t be doing that again

I wasn’t aware you can siphon against gravity, but I suppose the mechanical aid of the ATO pump caused enough low pressure to do it ?

I don’t think you can siphon against gravity. Water will move to lowest point.

 

[LeftyReefer]

My ATO also overfilled my tank several times, but it only seemed to happen at night....

I assumed it was the nocturnal snails coming out and causing an issue with the optical sensor at night. So I just came up with an easy solution. turn my ato off at night.
So I just plugged my ATO into a smart plug and set it on a timer to only run during the day. At night, when my tank lights shut off, the smart plug shuts off the ATO too. It comes back on when the tank lights come back on the next day. Has not overfilled again since. Most of my tank's evaporation happens during the day, when the temps are warmer and all the lights are on. not much evaporation at night, so I don't get much if any swing from doing this.