Automatic Top-off Issue

[eggman]

Hello everyone, I am far from being the Do-it-yourself type of person, although I try to get by as best as I can. I am having a siphon issue with my ATO system I am trying to install. I have the reservoir located above my tank with a maxi-jet 400 pumping a 1/2" tube into my sump. Basically, here's the issue: once the flaot sensor activates the pump, it continues to run after the power is cut from the pump due to the natural siphon. Am I screwed or is there some type of cut-off valve that I can install to counter-act the siphon? I truly apologize for my ignorance, I am learning new things in reef-keeping every day....

Thanks for your guidance here!

Sincerely,
Alex

 

[parsonsaj]

I had a similar configuration. I added a venturi input, which allowed air to enter the tube once the back pressure from the pump stopped. This would break the siphon and keep it from emptying the reservoir.