lol, sorry about that. I guess its different when you already did it. I'll try to do my best in explaining this. You should also have some knowledge of how the ordinary overflow box works... BTW, this is a hangon overflow box.
1st picture shows a sort of diagram between the ordinary overflow box and the one implemented with pvc ( distorted side view). As you can see, when the water level is above the upside down U, excess water will be drained. If the water level is below the upside down U, then the water stays still until the water level rises and pushes the water over the other side. The siphon wont break because there will always be water on both sides.
Now, lets apply this. Some pictures might not be the best for showing how the system works, but its all I have. I took these when I was testing for leaks and if it worked.
So, the 2nd picture shows the front view. There are a total of 3 water intakes which are marked with red. The green arrows show the water flow thats transported through the siphon.
3rd picture shows the other side. In here, you can see how the water flow is sent downwards and then must make its way up so it can finally be sent to the sump. Notice how this creates like a box that will always hold water. So if the water level drops, there is always water on the other side and wont break the siphon.
So whats the valve and the twisted upward tube for? Well, the valve is so that you can fill the overflow with water so that you can start the siphon. The other thing you dont need it, it will still work if you leave it on but it will "suck" less water. Its just something I was experimenting with.
You can also place valves at the end to regulate how much water you want, thats what I did.
I hope this helps. The pictures should give you an idea on how to assemble it, if not, then I'll try making a step by step diagram on how to make one. But remmember that this can be improved so that it takes less space and works better. Please excuse my spelling and phrasing.
