U-Tube Siphon for overflow box problem

[foxandhound]

Hi,

I am having an issue setting up my siphon for my overflow box. I keep getting a small air bubble in the center of the U-Tube which in a few days grows to a large bubble and slows down the flow allowing the water level in the overflow box to creep up.

I use a technique I learned on YouTube where I insert an airline into the U-Tube a little more than halfway and suck air to start the siphon. I then try to crimp the airline as I am removing it from the U-Tube but it seems that some of the air from the airline escapes into the U-Tube allowing the bubble to form.

What am I doing wrong???? Why is the bubble growing in a matter of days???

p.s I clean my prefilter sponge and filter sock in my refugium every few days which I have found also helps to keep a steady flow.

Thanks for your help

[Percula9]

Take a power head pump and shoot water up the tube on the tank side. This should prime the syphon and prevent your air bubble from forming.

[foxandhound]

So I would do that instead of the technique I described??? If so, can you provide a bit more details, like how far do I insert the airline from the tank side?

Any vids showing that?

sorry, novice reef keeper here???

[j tavares]

Try a stronger return pump to keep flow going thru the siphon tube constantly and I hope that will solve the problem

[Percula9]

Insert the output of the pump into the tube directly. There is no airline involved. Fill the tube with water from the pump until it is primed for the syphon to begin.

[jdander2]

You can also get something like an aqua lifter. Attach one of the tubes into the u-tube and the other down the overflow and it will suck the air bubble out without you having to ingest saltwater.

You can have it either running all the time, or put it on a timer to run once a day to remove any air bubbles. I had one of those overflow boxes, and from my experience, you'll always be battling the bubble that forms in the u-tube.

[zigzag1]

Originally Posted by j tavares

Try a stronger return pump to keep flow going thru the siphon tube constantly and I hope that will solve the problem

This... 100 percent this. Not sure what everyone else is thinking. wow..

[j tavares]

Thanks ZIGZAG that would do it

[TimeConsumer]

Originally Posted by zigzag1

This... 100 percent this. Not sure what everyone else is thinking. wow..

+2

My 600gph Lifereef overflow starts to get bubbles building up below 200 gph.

[moondoggy4]

Also you can tilt the in flow box to the far side where the U-tube is not and that will slow down the bubbles from getting in the u-tube.

[fishgate]

Originally Posted by TimeConsumer

+2

My 600gph Lifereef overflow starts to get bubbles building up below 200 gph.

+3 - as stated, with proper flow, you won't get bubbles in the u tube! Mine starts to form bubbles when the water level lowers due to evaporation. Once I add a gallon or so, it is right back to no bubbles.

[jcw]

I think the sponges and the short standpipe that sits on the outer drains slows drainage enough to prevent bubbles from being created in the siphon.

But i agree wit the above posts, increasing the return will fix it too.

I put a valve on the outflow drain which i've read is a no no but everything has been ok.

[matt888]

Originally Posted by jdander2

You can also get something like an aqua lifter. Attach one of the tubes into the u-tube and the other down the overflow and it will suck the air bubble out without you having to ingest saltwater.

You can have it either running all the time, or put it on a timer to run once a day to remove any air bubbles. I had one of those overflow boxes, and from my experience, you'll always be battling the bubble that forms in the u-tube.

Do THIS. I implemented it a few months back with success.