Overflow Siphon Break ???

[gio28]

i just got my eshopps pf800 overflow for my sump and the first thing i do is find a video online of it talking about how the u tube it comes with can fill with bubbles and eventually break the siphon...so im stressed now lol.
i guess that if bubbles get sucked into the u tube then they accumulate and over time form a huge bubble that will break the siphon...is this true or just lame lame video of a guy that doesnt know what hes talking about?

 

[scsinet]

It's true.
It happens from insufficient flow rates. What happens is that bubbles occasionally get drawn into the overflow. If the flow isn't fast enough to "flush" those bubbles through the U tube and out the other side, they end up trapped in the tube where they join with other bubbles over time.
If you run your overflow at 70% capacity or more, it shouldn't be a problem.
If it is a problem, it may help you to know that the bubbles accumulate over time. It's not like you start it up, go to the bathroom and come back to find a flood... it usually takes days. I have one on a nano tank in my office at work that does this, and it never happens quickly enough to become a problem in my absence... even over weekends. I generally just have to re-pull the siphon about once every week or two.

 

[gio28]

oh ok thats a huge relief. my overflow is about 800GPH and i know thats dependent on what my return pumps power is...i have a via aqua that pushes 1057 gallons and at 4' it will push approx 600gph not including 2 45 degree elbows and 2 or 3 90 degree elbows which may give it less gph.