ATO in Return Chamber with a DC Pump

[hannernanner]

I'm setting up a Tunze ATO for my new system, and from all I've read, the sensor should go in the return chamber. The return chamber is the only chamber of the sump with water level that changes regularly. How is this not a recipe for disaster? With the newer DC variable return pumps, a change in the speed of the pump could change the water level in the return chamber, right? So if I put my return pump in "feed mode" lets say, would it not increase the level of water in the return chamber and set off the "high water" alarm on the ATO? By contrast, if I turned the pump to a higher speed, the level in the chamber would drop, theoretically kicking the ATO on even when it's not needed.

How does this work in practice? Am I over-complicating? TIA

 

[Ribo15]

Yes the feed mode will activate the high alarm in most people systems. You have to either use an apex or the like to disable power to the ATO during feed or have the high alarm sensor mounted higher in the return chamber than the water level will reach. This kind of defeats purpose of having one though. And yes the speed increase of the pump will kick on the ATO but I think most people get their pump dialed in and leave the settings alone unless for maintenance or feeding. My tunze ATO kicks on many times a day.

 

[hannernanner]

Yes the feed mode will activate the high alarm in most people systems. You have to either use an apex or the like to disable power to the ATO during feed or have the high alarm sensor mounted higher in the return chamber than the water level will reach. This kind of defeats purpose of having one though. And yes the speed increase of the pump will kick on the ATO but I think most people get their pump dialed in and leave the settings alone unless for maintenance or feeding. My tunze ATO kicks on many times a day.

Thanks for the quick reply! Yeah I figured a controller would be the answer. So really, no benefit to a DC pump unless you're running it on a controller it seems..

 

[Ribo15]

Well I have a DC pump and it currently doesn’t integrate with my apex I like the fact that I can choose a flow that seems to be best balanced for my sump turnover and when I go into feed mode a simple click of a button ramps the pump down to minimum speed for 10 minutes then slowly ramps back up. Plus the energy savings and not having 120v AC in the tank is nice also. Happy reefing!