Can I position my ATO container on top of the sump

[Kalitk0]

I have Red Sea ATO+ and I want to put my ATO container on top of my sump but I am not sure if the flow will stop when the pump stops or it will create a syphon? And another question is it safe to put it on top of the sump in terms of weight will the sump be OK. THe container is about 20l.

Is there anybody with similar setup. Please advice. Thank you

 

[Gtinnel]

I can’t say about the weight, but if the outlet of the ATO pump is below the later level of the ATO container it will be a siphon.
The siphon issue can be fixed with a float valve, and then you wouldn’t even need the ATO. The float valve alone would regulate the water level.