losing siphon in overflow

[cafamore]

how can i make sure i donot lose siphon in overflow box. is there a self siphoning overflow. i dont want to take the chance of drilling tank to put in a bulkhead

i am concerned that if i lose the siphon i will have about 70 gallons of water on my wifes WHITE carpet. any ideas would be great i am looking to put in a larger overflow this one cant keep up with pump. so i have to regulate the flow.

[Doug1]

Which hang on overflow do you have now

[naser]

well mine has been on my tank runing for months.. i have stoped the return a bunch of times. and never has the overflow lost syphon.
www.lifereef.com
prefilter box is what its called.

[jegel]

The only 2 ways that I can think of that would cause a loss of the siphon is if the water level drains below the siphon tube intake or outtake which shouldn't happen in any overflow setup. The other way is if bubbles in the water accumulate in the siphon tube which could build up over time in a slow moving current and break the siphon. I've been running my overflow for almost a year and have never had this happen. I did howeveer have a siphon tube in my sump setup have this problem. No water was spilled though since there were 2 tubes and the second simply took up the slack of the first tube. This only happened to me because I just got a new skimmer which created a lot of bubbles in the sump. These bubbles never made it to the tank so no worries up top.

[ 03-01-2001: Message edited by: jegel ]

[gpohly]

I agree w/ Jegels comments except for the part that siphon can be broken by the water falling below the water tube outtake; that won't make a difference. To break siphon, gotta get air in the tube by one of two ways: bubbles entering, or intake falls below the tube.

It is possible to self-siphon. You can do this if:

1. Outtake tube is open to the air (or there is a small air vent drilled in the top of the siphon tube);
2. Water flow is high; and
3. You have a plumbing arrangement that allows the water level to exceed the heigth of the top of the siphon tube.

Great for science experiments, not likely in aquariums; the top of the siphon tube is usually above the top of the tank, otherwise you wouldn't be using a siphon system!

IMO, drilled tanks are not a bad thing, and coupled with overflow boxes and sumps, provide the very best assurance you won't flood you room in the event of pump and/or power failures.

Glenn

[gpohly]

Ya know, looking at the initial post...

How is it that it's your tank, and you are concerned about damaging your "wife's white carpet"?

Man, same phenomena in my house...I paid for the house, but damaging the carpet w/ salt water is definately not wifely acceptable on HER carpet. Guess that's also why her car is in my garage, and I get to walk to my truck in the rain.

Someone said it best in an earlier post...We are whipped. Ahh, love....

[cafamore]

YAEH AND SHE LETS ME SLEEP IN HER BED. AND I GET TO BRING HER MONEY AFTER A DAY AT WORK. HA HA..

just want to make sure i have no problems. is there a self priming everflow box out there

[Doug1]

The U tube siphons like the basic Amiricle and the LifeReef models are constructed so that both ends of the UTube are kept submerged to avoid breaking siphon. Once the power goes out it can only drain the tank down to the bottom of the slots in the inner overflow. As the water stops flowwing in its trapped in both sides keeping the UTube full
After power up the return pump puts water back in the tank raising the level causing water to splill into the overflow box causing it to siphon into the back box and down the drain. Very simple, very reliable if the flowthrough rate is close to the flowrate of the Utube diameter. You need velocity to keep occasional bubbles that get sucked into the siphon from accumulating and slowing it down further. ONce you have set one of these up they are simple to maintain and reliable starting. Mine have worked for a couple years with no failures.
The continous siphon like the CPR and upgraded Amiracle and such rely on a powerhead with a strong venturi action to cleat the air from the siphon passage. These overflows are usually rated at much higher flows But if the powerhead that suck starts it fails to come on when the power does you wont get auto start up My Sen 900 has a fitting that adds a venturi adaptor and hooking the siphon to that is the only way I would run one of this type of overflow. If the pump starts so does the siphon, other wise the risk is too great for me to chance