Originally Posted by
Jstdv8
http:///forum/post/3279424
Flower,
You have an overflow box on the inside with teeth on it that the water flows through to fill up the box. There is a U shaped tube that runs from the overflow box on the inside to a drain box about the same size on the outside.once you have the water level right in your tank and your sump/fuge and are ready to start moving some water you stick a hose up inside the U tube and suck on it just like you do to siphon gas out of your car.
You will see the tube quickly fill with water and then you pull out your little siphon hose and now you have a permanant siphon between the box on the inside of the tank and the box on the outside of the tank.
The box on the outside has a pipe going out the bottom that drains the water down into the sump.
The pipe that forms the drain actually sticks up inside of the outside box a few inches so that the box has to fill up with water a few inches before it is able to flow into the drain. This keeps some water in the bottom of the outside box at all times which in turn keeps the bottom of the U-tube under water. As long as the U-tube is under water on both the inside and the outside boxes it will never lose siphon.
So even if a poweroutage happens and your return pump stops working as soon as power is restored the tank will fill back to the normal level which is dictated by the height of the insied box in your DT and when water starts filling that box up again the water starts flowing through the U-tube again and down into your sump.
2 downsides to it.
1.) its not the prettiest thing in the world to have a box in the corner of your beautiful tank.
2.) if You bump the U-tube during maintenance and it pops out of the box and loses siphon yu have to do the sucking thing again.
as far as the sponges in the overflow I don't use them anymore. I just let the stuff run down into the sump and suck it out during water changes.
thanks, i couldnt think of a good way of describing an overflow box...lol