ATO Malfunction

[Denver45]

Hey All,

I had an ato go haywire the other day, not sure why, but it didn’t top off for a few days then dumped a bunch of RO into my system all at once. Had a pretty massive salinity swing in 24ish hours 1.029 to 1.025 and now have some unhappy inhabitants. Looks like so far I’ve lost two snails but more so, I’ve got a couple corals looking rough. Do you all think they might pull through or should I pull them before I have to deal with decay? Pictures attached. Thanks!

 

[HankstankXXL750 Verified Sponsor]

I wouldn’t pull them at this point. Watch them closely and hopefully they pull through. From the pictures they look upset but don’t show tissue loss. If they start to really decay, pull them and do a partial water change.

 

[Glenner’sreef]

So are you saying the salt was at 1.029 the diluted down to 1.025? If so the second number is more where you want to be.

 

[Denver45]

So are you saying the salt was at 1.029 the diluted down to 1.025? If so the second number is more where you want to be.

Yeah I usually keep it around 1.025. The ato didn’t keep up with the evaporation for a couple days, then dumped a bunch of freshwater in all at once. I’m back at 1.025 now so manual top offs until the new ato gets here.

 

[TheBear78]

What did you do to address the issue when you realised that the salinity was 1.029?

 

[Glenner’sreef]

Not knowing what ato brand you got or are getting, but the ones with sensors can cease to work properly if they get gunked up with film algae. It’s good to clean then occasionally.

 

[FishyDP]

I have never had luck with sensor ATOs. Salt creep/algae on the sensor tends to be an issue. I prefer using dosing pumps to top off, or a quality gravity fed float valve. With the dosing pump, I usually have to adjust the rodi water dose every 2-3 months/seasonly as evaporation rates change.

+1 your corals may push through, just make any adjustments slowly. Maybe run some activated carbon if your corals are ticked off and releasing toxins.

 

[bvanfish]

I have never had luck with sensor ATOs. Salt creep on the sensor tends to be an issue. I prefer using dosing pumps to top off, or a quality gravity fed float valve. With the dosing pump, I usually have to adjust the rodi water dose every 2-3 months/seasonly as evaporation rates change.

I’m becoming more interested in this. How big is your tank / amount you “dose”

 

[HankstankXXL750 Verified Sponsor]

Yeah I usually keep it around 1.025. The ato didn’t keep up with the evaporation for a couple days, then dumped a bunch of freshwater in all at once. I’m back at 1.025 now so manual top offs until the new ato gets here.

How many gallons is the tank? Does it have a sump? .004 is a huge swing, if using a sump I would think you were sucking air in your return. If it happens again, I would add water more slowly to gently lower the salinity. That being said, the 1.029 is probably harder on the corals than the drop to 1.025. But with corals being largely made up (or filled) with water they may react worse to salinity swings.

 

[FishyDP]

I’m becoming more interested in this. How big is your tank / amount you “dose”

I currently have an empty 125g with 40g sump waiting to be set up. I will likely use the dosing top off method with a jebao 4 channel dosing pump dedicated for top off. I will use all 4 channels just for ato. 2 channels for rodi and 2 channels for kalk. I used this on my last setup which was about 270g. I dosed roughly a gallon/day in that system. The more water volume you have the more channels I would use as the doser will get a heavy workout and you dont want to burn it out. The amount varies as evaporation changes. In the humid months less evaporation and less top off. Cold months much more evaporation with dry air from home heat. To calculate, just figure out your current daily evaporation rate in gallons and convert to ml, and dose that amount spread out by the # of dosing channels.

This is my go to for ato, not as much babysitting required as compared to sensor atos/float valve, in my experience.