How do you keep a overflow box primed?

[fishfreak1242]

Whenever I shut my return pump off to my sump to test in case of a blackout and my overflow box loses siphon, it doesnt get the siphon back when I turn the return pump back on. Does anyone know how to keep it primed? I made my the overflow myself using two specimen boxs with slits in one of them and a u-tube.

 

[scsinet]

It sounds like you may have a design flaw in your overflow box. Can you take some pics and post them?

 

[fattony]

the U tube style boxes are the best IMO.. mine never lost siphon, not even once...

 

[rotarygeek]

You need a baffle in the chamber outside of the tank that comes up higher than the bottom of the overflow tube. This keeps just enough water in the back chamber so you don't lose your syphon. Water should only go down to the bottom of the slits in you skimmer box, so that shouldn't be a problem.

 

[hurt]

It sounds to me like you need to put in longer drain pipes in the box that sits outside your tank. This will raise the water level in both boxes so no air can get in and break siphon. If you post a picture of both boxes when you turn your return pump off, that would help to see if this is the case.

 

[kingsmith]

Originally Posted by RotaryGeek
http:///forum/post/2746059
You need a baffle in the chamber outside of the tank that comes up higher than the bottom of the overflow tube. This keeps just enough water in the back chamber so you don't lose your syphon. Water should only go down to the bottom of the slits in you skimmer box, so that shouldn't be a problem.
+1

 

[fishfreak1242]

Originally Posted by Hurt
http:///forum/post/2746164
It sounds to me like you need to put in longer drain pipes in the box that sits outside your tank. This will raise the water level in both boxes so no air can get in and break siphon. If you post a picture of both boxes when you turn your return pump off, that would help to see if this is the case.
I will try that. Right now I have the drain pipe hooked up with a 90 degree elbow on the end and it is just a little shorter than the end of the u-tube. Thanks for all of the other responses. I wont be able to get any pics because my camera recently broke. I will try to describe it as best as I can.

 

[hurt]

Originally Posted by fishfreak1242
http:///forum/post/2746401
Right now I have the drain pipe hooked up with a 90 degree elbow on the end and it is just a little shorter than the end of the u-tube.
That is most definitely your problem, put in a taller(longer) drain pipe in the outside box before the bulkhead and you will have no problems.