Coral Crash from an AWC failure. Any thoughts on preventing this with Neptune APEX Alarms?

[Texastravis]

I lost my corals a few months back from an auto water change failure on my 120 gallon tank. I have a 55 gallon barrel of RODI water and a 55 gallon of fresh salt water that I remake once a month. My AWC system was set to 1.5 gallons per day water change at night with the Neptune DOS. What happened is the 1/4" line for new salt water developed a slight crack so the DOS was not dosing new salt water but it was removing the 1.5 gallons per night. The difference was being made up by my ATO pump.

Any ideas on how to alarm or prevent this with the APEX? I was hoping I could put a power usage alarm with the ATO so that if it was on above or below the average it would catch a failure of the AWC, however, it seems that after fiddling with this the Apex will only monitor max and min wattage (on/off) type usage on the ATO outlet. I was thinking I could set this up as max/min ATO run times but I am not sure if that would work either since the DOS likes to run in 10 min on off increments. I think It would only work if I could set it up to monitor total run time of the ATO throughout the day, not each run cycle. Is this doable? What are others doing?

 

[Texastravis]

I will add that the way I manually check to make sure my AWC is working properly is once or twice a week I pull up the AWC power consumption graph and make sure it is running about the same amount of time as it usually does. I also periodically check my barrel levels outside to make sure it is depleting.

 

[Js.Aqua.Project]

So the only two methods I can think of would be to use a salinity probe (which can be unreliable sometimes) which would notify you and disable the ATO if the salinity were to go below a set threshold.

Or the other way would be to use one of their Liquid Level Sensors (LLS) to keep closer tabs on the level in your barrels. Then the trick would be to figure out how to program the alarm to notice if too much RO was used that day.

 

[Rob Biederman]

I have the Red Sea ato and it shows the daily amount added by my top off. And +1 on the salinity probe it was the first thing that popped into my head

 

[tsharpe291]

I lost my corals a few months back from an auto water change failure on my 120 gallon tank. I have a 55 gallon barrel of RODI water and a 55 gallon of fresh salt water that I remake once a month. My AWC system was set to 1.5 gallons per day water change at night with the Neptune DOS. What happened is the 1/4" line for new salt water developed a slight crack so the DOS was not dosing new salt water but it was removing the 1.5 gallons per night. The difference was being made up by my ATO pump.

Any ideas on how to alarm or prevent this with the APEX? I was hoping I could put a power usage alarm with the ATO so that if it was on above or below the average it would catch a failure of the AWC, however, it seems that after fiddling with this the Apex will only monitor max and min wattage (on/off) type usage on the ATO outlet. I was thinking I could set this up as max/min ATO run times but I am not sure if that would work either since the DOS likes to run in 10 min on off increments. I think It would only work if I could set it up to monitor total run time of the ATO throughout the day, not each run cycle. Is this doable? What are others doing?

the exact same thing happened to me with DOS. luckily I caught it in time and that was the last time I relied on the DOS for awc

 

[pres10c]

the exact same thing happened to me with DOS. luckily I caught it in time and that was the last time I relied on the DOS for awc

What are you using now?

 

[tsharpe291]

nothing at the moment, doing my weekly the old fashion way.
luckily I have my sump and a secondary tank in the basement so draining and refilling are quite easy.

 

[ca1ore]

Although the salinity probe isn’t the last word in reliability, it will generally catch larger swings in values. Another option is to store the old water so that you can visually confirm that water is both being added and removed. I use two brute containers, one for NSW and the other for OSW. I have level switches in both, so when the NSW alerts me that it’s empty I am able to visually confirm that an equal mount of OSW has been removed.

 

[Malum Argenteum]

I don't do AWC*, but:

Consider setting it up so the AWC is only running during a certain time window. During that window, program the ATO to 'off'.

Then, program to run the drain and replacement pumps however you want but monitor them with float switches (the ones that the ATO circuit uses, probably) to detect if the water level is too high or too low during the duration of the AWC cycle. (An an aside, think through what will happen when one of the floats sticks, and build in some failsafe against that failure condition.)

After the AWC cycle is complete, then programming restores the normal functionality of the ATO and disables the AWC until the next scheduled time period.

Another tip is to only hook up as much water to any automated system that a failure won't be (as) catastrophic. My ATO bucket is ~5g on a ~110g system (and so has an average of 2.5g in it, depending on when I last filled it), and my sump could hold all that.

*I do a semi-AWC, whereby one of the feed cycles sets the ATO to 'off', and uses the ATO float switches to trigger a pump that moves premixed water up from a vat in the basement. I drain manually, but this setup saves me hauling buckets (it also has the virtue of only operating while I'm standing there siphoning and keeping an eye on things).