Bean's overflow??

logans · Jun 4, 2011

So let me ask, if I loose power doesn't the siphon continue and overflow my sump? And how do I know where to position my 3 standpipes in the sump? I'm using a 20l with a 10g sump.
I don't know how to calculate my sump so there is no overflow issues. Please help!

aalvarado87 · Jun 4, 2011

its only going to siphone to a certain level its not like its going to draint he whole tank. Are you using an overflow box?

Netta Fish · Jun 4, 2011

it will siphon untill your returns are out of the water. a lfs store had a solution to this and it was to drill a small hole in the 90 of the return this breaks the siphon. as for your stand pipe i have on low and the other two high. this leaves the one pipe taking the majority of the water the other two are there in case the first one clogs this also stops the fluctuating gurgling you hear in the sump.

Troylee · Jun 4, 2011

As soon as the water level gets to the lowest point of the overflow it sucks air and breaks the siphon and stops... Do you have a internal or external???? Shoot a pic if ya can....
If you wanted to do the math is easy take lxwxh and divide it by 231 =x now take x and divide by the heigth say it's 2.1 now that means for every inch of water in your tank there is 2.1 gallons, if the lowest part of your overflow is 2" down your gonna have 4.2 gal wash back.... For the sump same thing let's say it measures 16x12x12 so that equals 2,304 divide by 231 that's 9.97 gallons now divide that 9.97 by 12 the height so for every inch of water in the sump you have .83 gallons.... Make sense now???? If you ran your sump at fifty percent you would have enough for 5 gallons wash back..... Hth please feel free to ask if not lol... I know I can be confusing sometimes if not all the time...:tongue:

logans · Jun 4, 2011

Ok. I see how it works now. I is going to be internal. I'm building it myself out of acrylic. I was going to run the overflow box the length of the 20l. I'm trying to figure out how far down to drill my holes from the top of the tank. Also, can i use 3/4 pvc instead of the 1.5? I feel 1.5" is a lot for a 20l.

Troylee · Jun 4, 2011

I would use 3/4" bulkheads with 1" plumbing myself it should work like a charm.... Drill them close to the top as possible grab your bulk head and set it against the tank 1/2" down from the outerflange and mark the center... I will get some pics of mine if you need when I get home... Actually it don't matter where you put them if the box is inside it skims the surface just set the top of the box where you want the water line... Hth

logans · Jun 4, 2011

Thanks Troylee. Can I use the 3/4 bulkhead and 1" pipe for the return also? Where is a good place to get bulkheads? Lowe's has bushings. Is that the same? Should I go with glass holes for the drill bit and would that be a 3/4" bit? A guy at work told me to get 7/8" bit.

walkerbrody · Jun 5, 2011

To keep from overflowing your tank, fill your tank from the top with the return pump off. Fill your tank until your sump is nearly full (it will flow down your overflow filling the sump). Turn on your return pump. The level in the return section of your sump will drop due to the water in the plumbing. Mark the water level of your return section with a sharpie and make sure you never fill your sump beyond this level.

logans · Jun 5, 2011

Thanks walkerbrody.

walkerbrody · Jun 5, 2011

you are welcome

UncleJT · Jun 6, 2011

logans said:
Thanks Troylee. Can I use the 3/4 bulkhead and 1" pipe for the return also? Where is a good place to get bulkheads? Lowe's has bushings. Is that the same? Should I go with glass holes for the drill bit and would that be a 3/4" bit? A guy at work told me to get 7/8" bit.

A 3/4" bulkhead requires a 1-1/2" hole saw (bit). You can get both the hole saw and bulkhead from glass-holes.com.

scott26 · Jun 6, 2011

I have a bean system as well on my 90 gallon surfline. I would not use small holes as siphon breaks rather just make the returns terminate just below the water level of the tank. The reason I do this is because eventually when the planets align your small siphon break holes will get clogged (snail, algae, food) and flood your sump.