I have an old school style overflow box with two U tubes on my 180 and one mildly annoying recurring problem is when one tube or the other somehow winds up with an air pocket in the curve of the tube,the water still flows but it seems to be lessened when this occurs...has anyone experienced and dealt with this issue?
Issue with trickle filter overflow tube.
- Thread starter krichardson
- Start date
When I used overflow boxes years back, I had the same air bubble buildup problem, especially when trying to use more than 1 U. Tube
I made better progress when I found a 1 1/4" (above) inner diameter U Tube on the internet somewhere.
But even then, U tubes always made me nervous, and in the end, I just learned to drill glass tanks, and never went back after picking that up.
I made better progress when I found a 1 1/4" (above) inner diameter U Tube on the internet somewhere.
But even then, U tubes always made me nervous, and in the end, I just learned to drill glass tanks, and never went back after picking that up.
I personally have the same acrylic overflow box on my 180 diy trickle filter sump. I tried two U tubes had the same problem. Now utilize one for over 18 years with no issue.
Only thing I can think of is adding more water to the aquarium and see if that helps.
Only thing I can think of is adding more water to the aquarium and see if that helps.
Did you get a larger diameter tube as
duanes
did? I guess I could try keeping the water level in the sump a bit higher and see how that goes.This explains the physical phenomenon that is happening in your tube and a few solutions. Another thing I've seen people do is drill a small hole at the top of the curve and push a smaller tube in. Seal the hole to prevent leaks and attach a valve of some time to the smaller tube; open to release air and close to keep flow going 100%. Basically a bleed line for your tube/pipe.
That's a cheap and easy solution, but if you add that tube/valve arrangement, it won't act as a bleed valve all on its own. Opening the valve will merely suck more air in through the open valve as the water falls out of the tube completely, breaking the siphon. It requires suction to be applied to the small tube as the valve is cracked open. You must continue to suck to remove the trapped air; once you start to get water in the small tube, you can then close the valve knowing that all the air is out of the siphon.
You're right, I forgot to mention most people use a small medical syringe connected to the tube at the end to provide suction to remove the air through the bleeder valve.
Hey,thanks for sharing that interesting and informative video.
About 20 years ago I was experimenting with a CPR overflow after picking one up used.
It could never hold siphon without help.
As you can see above, and below I attached the venturi port of the powerhead with airline tube, to a drilled port in the overflow box.
As long as the powerhead was running and the venturi would suck air, the siphon in the overflow held.
It could never hold siphon without help.
As you can see above, and below I attached the venturi port of the powerhead with airline tube, to a drilled port in the overflow box.
As long as the powerhead was running and the venturi would suck air, the siphon in the overflow held.