Bubbles in U tube

[mag395]

I have recently set up an overflow box and a sump. Sometimes it siphons good, other times small bubbles get stuck in the U tube and eventually turn into one large bubble. It's happening because as the water goes into the overflow box in the display tank, it makes small bubbles that get sucked up into the U tube.
Does anyone know any way to stop the bubbles? Maybe putting some kind of foam on the inside of the box?

 

[zx636r]

When I ran an overflow box I found the best way to get bubbles from not building in the U tube is to speed up the flow (return pump) going into the overflow box. When I had my return pumps ball valve cut back there would be times when one large air bubble would form. It was never enough to break the siphon but enough to make you a little uneasy. The more flow you have going into the overflow the faster it will move the bubbles through the pipe and the less likely of a chance of build up. At least thats IME.

 

[murph]

Zx is on the right track. Simply put you need a stronger return pump.

 

[maxalmon]

If a larger volume pump is not an option, use that really course foam block filter stuff, it's usually white and made for Aquaclear fileters, cut some to shape and line the inside of the overflow, don't pack it in, just remember to clean it from time to time.

 

[sly]

My U tube just barely misses hitting the bottom of the tank. I cut it long so that it would suck up water from the lowest point, where the air bubbles aren't... The shorter your U tube is, the more bubbles it will suck up.

 

[maxalmon]

Originally Posted by Sly
My U tube just barely misses hitting the bottom of the tank. I cut it long so that it would suck up water from the lowest point, where the air bubbles aren't... The shorter your U tube is, the more bubbles it will suck up.
Awesome observation

 

[pallan]

Originally Posted by Sly
My U tube just barely misses hitting the bottom of the tank. I cut it long so that it would suck up water from the lowest point, where the air bubbles aren't... The shorter your U tube is, the more bubbles it will suck up.
The bottom of the tank?

or the over flow box? if its the bottom of the tank whats to stop the overflow from empting your tank on the floor if the return pump quites/powerout and it overfills your sump?

 

[maxalmon]

Oops, maybe it wasn't such an awesome observation, I was thinking he ment the bottom of the overflow, but if it's the bottom of the tank, thats a disaster waiting to happen

 

[murph]

If the pump ain't strong enough the pump ain't strong enough. No matter how you go about it you run the risk of air collecting in the U tube and breaking siphon which means the contents of your sump will end up on the floor and your pump will burn up when it starts to run dry.
Invest in a new pump. The old one can be used to mix change water with.

 

[sly]

no i meant the bottom of the overflow sry

 

[mag395]

I got the bubble problem sorted out and I also opened the flow valve on the pump. Everything looks great.

 

[coachklm]

if you lower the intake overflow box(the box in the tank) there will be less large bubbles produced by the waterfall effect of water rushing into the box from the tank.

 

[mag395]

yeah, I noticed that. Thats how I got the bubbles out. Thanks for the help guys!