Back Siphon Question

[studmaster]

Okay, just creating my first sump and am trying to work out any possible failures. I am trying to figure out the back siphon issues in case the power goes out.

Currently I have a "Y" Loc-Line adapter going off in two directions from my sump return in the Display tank. In referring to the picture below, would the back siphon stop once air hit the top of output "A" of the locline, the bottom of the bend in ouput "A" in the loc-line, or the bottom of output "B" in the loc-line?

Thank in advance for any help. I would just simply test it out myself, but I ended up putting a check value in the return line as an added precaution and it won't allow me to check a siphon break.

[studmaster]

....sorry, assuming that the check value will eventually fail like everyone says it will.

[jasonrp104]

A (top of output)

Myself, I'd be safe and punch a hole or 4 before the Y adapter. A little extra piece of mind

[studmaster]

Originally Posted by jasonrp104

A (top of output)

Myself, I'd be safe and punch a hole or 4 before the Y adapter. A little extra piece of mind

The only reason I thought that maybe it would be the bottom of outlet "A" is that since it's curved down, the air wouldn't get through the tube until it at least reaches the top of the lowest part of the curve....then air could get through. Does that make any sense?

[celano]

Return lines are meant to agitate the water surface in the tank, not to supplement flow.
It doesn't matter how many fail safes you have if you put those return lines to far under water sooner or later your sump will overflow.

[jmking33]

Id put a few holes just above the "y" just to be sure. You can never be too safe.