Need some help setting up my ato

[DEE’S reef]

I got a hygger ato and I was wondering if anyone could help me what height should I cut the hose. Do I want the hose above or at the water line.

 

[CrewePD210]

I would say above the sump water line. If it ever got overfull, you would risk a back siphon. A check valve would stop it, but id want the air gap as well.

 

[DEE’S reef]

It came with a check valve so should I cut it a inch or 2 from the water line and add the check valve.

 

[exnisstech]

I don't worry as long as its above the water line with the return off and above the reservoir it will be good.