Hang on box overflow occasionally breaks siphon casuing tank to leak, help!

[xunkn0vvnx]

My hang on box overflow with U tube that siphons water from the tank occasionally (maybe once every two months) breaks the siphon because of bubbles from the tank getting sucked into the U tube. Can anyone recommend a solution to this? Once the siphon breaks, my return pump empties my sump into the tank causing a pain in the *** tank overflow leak problem.

[budbreak96]

There is something on the net. about the u tube set up. You add a tube on and drill a 1/16th hole in the add on one and it wont gurgle or overflow or nothing. Call waterworld in pensacola florida and ask for steve and ask him about it. He will tell you exactly what to do. (850) 477-3239

[143gadgets]

I think you need to push more water through that overflow box. Get a bigger return pump] and you should be fine. What are you using now?

[Wetline]

http://reefcentral.com/gallery/data/500/104870Siphon_drain.jpg Attach a aqualifter pump to the airline at the top. You could drill a hole in your existing U-tube and do the same thing.

Or you could do a durso style drain. http://www.dursostandpipes.com/BuildYourOwn/tabid/54/Default.aspx

[RicksReefs]

or the simple solution is to do what 143gadgets said, get a bigger pump to max out the overflow and the bubbles cruise right through.

[sjm817]

Drilling a hole in a siphon tube creating an air leak is not a good idea. You would turn the overflow into an unreliable CPR type overflow. If you are accumulating bubbles, you need to increase the flow. You dont need to max it out. Since it takes a couple of weeks for you to accumulate air, you are very close. You need just a little more. You could increase it with a larger pump, or maybe just improving the pluming back to the tank. Increase the diameter of the plumbing, reduce the number of fittings, etc.

[das75]

<a href=showthread.php?s=&postid=13012085#post13012085 target=_blank>Originally posted</a> by Wetline
http://reefcentral.com/gallery/data/500/104870Siphon_drain.jpg Attach a aqualifter pump to the airline at the top. You could drill a hole in your existing U-tube and do the same thing.

Or you could do a durso style drain. http://www.dursostandpipes.com/BuildYourOwn/tabid/54/Default.aspx

Even seen a MJ1200 setup in the display then the venturi tube tying into the high point of the U-tube to suck out any air that might accumulate.

[Toddrtrex]

<a href=showthread.php?s=&postid=13012277#post13012277 target=_blank>Originally posted</a> by sjm817
Drilling a hole in a siphon tube creating an air leak is not a good idea. You would turn the overflow into an unreliable CPR type overflow. If you are accumulating bubbles, you need to increase the flow. You dont need to max it out. Since it takes a couple of weeks for you to accumulate air, you are very close. You need just a little more. You could increase it with a larger pump, or maybe just improving the pluming back to the tank. Increase the diameter of the plumbing, reduce the number of fittings, etc.

Quoted for importance.

[jdieck]

If the overflow box is oversized for the return flow or tank size, increasing the flow trough may not always be possible so...
http://reefcentral.com/gallery/data/500/18470External_Overflow.jpg

Means to provide for removal of trapped bubbles needs to be provided as stated above.
Diagram of overflow box with aqualifter pump to prevent bubbles trapped to interrupt flow.
http://reefcentral.com/gallery/data/586/18470Overflow_w_lifter.jpg

[MrSandman]

an even cheaper solution may be perhaps buying a slightly smaller diameter U-tube. The water going through the tube would travel faster in a smaller tube versus the larger one thus forcing those little air bubbles through. Just a thought.