Dual u-tube HOB overflow

[escape2thewater]

Is this possible? Does anybody use one? I see one in this pic from swf.com but I have experimented with this idea for hours & hours and never have got it to work. My issue is when power is cut, the siphon breaks on one of the tubes then therea a problem when it comes back on...a big overflowing mess! If you know the secret please chime in! I have found that my overflows flow waaaaaaay more water with 2 u-tubes, like almost twice as much!
Escape
the link:
https://www.saltwaterfish.com/vb/sho...54&postcount=36

 

[escape2thewater]

ok the link didnt work so heres a pic.
Escape

 

[squidd]

For awhile there I ran a three tube overflow...with different size tubes...
740 measured gph thru a 1" bulkhead...
The "secrete" if you want to call it that is properly sizing the tubes to maintain siphon while providing the increase in flow...but then you need your standpipe to match...:thinking:

 

[lepete]

Hmmm.... Where'd u get the overflow? It looks like 2 speciment containers glued together. You might not have a properly built overflow...
Is there air build-up in the u-tube normally? Is there microbubble in the main tank? How does air enter once the power goes out?

 

[squidd]

Originally Posted by lepete
Hmmm.... Where'd u get the overflow? It looks like 2 speciment containers glued together. You might not have a properly built overflow...
Actually, that's a pic of one of "my" DIY overflows...It is made of two specimen containers a bulkhead, U tube (or two

) and a DIY Durso style standpipe...
It does work perfectly fine...
escape2thewater is trying to duplicate the results on his "Store Bought" overflow and not having any luck...at least I think his is store bought..??

 

[escape2thewater]

Yes mine is store bought. Ive been trying to increase the flow in my tanks. So if I can get the u-tubes to work correctly then I can run my returm pumps wide open and get more flow. Anyway Squidd, how do you figure out what size tubes you need? Is there any methodology to it or do you just play with it until you find the right fit? And how does the standpipe play a role in it? Is it just being able to flow enough to keep up with the increased water flow or is there more to it?
Thanks,
Escape

 

[escape2thewater]

[QUOTE=lepete
Is there air build-up in the u-tube normally? Is there microbubble in the main tank? How does air enter once the power goes out?
there is no build-up of air in the tubes or main tank. I have no idea how the air enters after shutdown but it does somehow. What happens is one of the tubes will break siphon then when the pump starts back up it will overflow. Thanks.
Escape

 

[az]

this is a easy fix!
in your tank you need to set the box so the water flow from the tank stops so you do not over flow your sump or your tank after power comes back on.... right?
well to do this your box on the inside of the tank has to be set to the right height in the tank to stop the flow into the syphon box. then the water flow will stop.
To start it back up again turn on the pump the water flows back into the tank and into the syphon box. Now where most have the problem. the tubes are not flowing down. ARRRRRR they say and they want to start it all over again.
Easy fix:
Take a small diam. hose 1/4" about and put it into your feeder tubes about 50 to 60% to just past the bend on the down spout side. then run the other end to were your pump pull the water into your tank. instant syphon. for every tube you use to feed the tank do the same thing.
But the key is the small dia. tube for the syphon and making sure the box on the inside of your tank is set to the right height.
hope this makes sense and helps!

 

[squidd]

AZ, not quite following your description here...??
To which pump are these 1/4"lines ? How do you get thru standpipe to U tube...?
Can you provide a drawing or better yet a pic...?

 

[squidd]

Originally Posted by escape2thewater
Yes mine is store bought. Ive been trying to increase the flow in my tanks. So if I can get the u-tubes to work correctly then I can run my returm pumps wide open and get more flow. Anyway Squidd, how do you figure out what size tubes you need? Is there any methodology to it or do you just play with it until you find the right fit? And how does the standpipe play a role in it? Is it just being able to flow enough to keep up with the increased water flow or is there more to it?
Thanks,
Escape
U tube sizing... https://www.saltwaterfish.com/vb/show...=sizing+u+tube
Standpipe does play a roll in setting "standing" water depth (power out)...do you have a Durso style or straight standpipe...?
Also, check water depth on inner chamber, look for "drop" that causes waterfalls that cause air to break/slow siphon on startup...
Watch on/off cycle ...when does the air build up...I'm thinking right at startup due to waterfall mentioned above...
Raising water level in inner/outer chambers should eliminate...???

 

[lepete]

Originally Posted by Squidd
Actually, that's a pic of one of "my" DIY overflows...It is made of two specimen containers a bulkhead, U tube (or two

) and a DIY Durso style standpipe...
Oh dang... sorry Squidd... I thought that was the OP's pix.

 

[escape2thewater]

Thanks Squidd, that makes so much sense! I do think that the siphon is breaking b/c the inner box is too high or the level of the outter box is too low now that you mention it. I will try to adjust them and play with it a little more. Thanks again. BTW I am running a straight standpipe currently.
Escape

 

[psusocr1]

i use a dual tube overflow with 2 lines drawing my water out. if you want a pic just let me know

 

[escape2thewater]

Originally Posted by psusocr1
i use a dual tube overflow with 2 lines drawing my water out. if you want a pic just let me know

Yes I would love to see a pic of how that works, I am having a hard time seeing it in my head.
Thanks,
Escape

 

[psusocr1]

Escape,s orry it took so long heres the pics of my overflow, i hope this is what you were looking for. let me know if you want to see anything else.