DIY overflow siphon problem

[ward1066]

I made a DIY overflow and sump last weekend, everything seems to work OK but when I test it by unplugging the pump the siphon breaks when the water gets down to the outflow tube and air is somehow getting sucked back into my overflow.When I plug it back in the siphon on the overflow does not start. Is there a way to fix this? I have a video of my setup in the video section
http://www.monsterfishkeepers.com/forums/showthread.php?t=259409


I tried setting the outlflow lower but then too much water would back siphon through the pump

 

[ward1066]

here is some pics

 

[Ficious]

Im 100% unfamiliar with these but i really like your idea of putting the sump through the wall like that...great work

 

[ward1066]

I am beginning to wonder if my overflow bottom U's are too short,,, I wonder if i made a bigger overflow with longer U's if it would be less likely to suck air in when the siphon breaks. Air is getting in the top U and I have to reprime it and suck the air out

 

[KaiserSousay]

Probably just my ancient eyes. You do have a check valve on your siphon starter tubing?

 

[ward1066]

Probably just my ancient eyes. You do have a check valve on your siphon starter tubing?

yep, I remade the overflow longer last night and it works now

 

[hndakd]

yep, I remade the overflow longer last night and it works now

excellent. just what i was going to suggest.

 

[ward1066]

thanks everyone, heres my final setup


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