Tunze ato

[Rmckoy]

I’m not sure if this is actually possible .
My Mrc skimmer shuts off when the collection cup is full .

as it shuts off .
the level in the sump raises.
I woke up this morning to my freshwater container overflowing

does the tunze pump backwards to lower the level if the water level is too high?

 

[Reef.]

It’s not the pump, it sounds like a back siphon, few reasons it happens, sounds like your ato tube went under water when the sump filled when the skimmer shut off, just raise the ato tube higher than that level.

 

[Water Dog]

Yeah, sounds like a back siphon issue. Always keep the ATO fill tube outlet higher than the water level in your ATO reservoir and be sure to maintain an air gap. Is your sump a good distance above the ATO reservoir?