well... i did some experimenting and came up with this design for an EXTREEMLY cheap and EASY overflow that handls about 600 gph
. THe last image attached below is the whole unit stretched out so you can see how things are linked together. The other two are to show you how it looks before it'll be attached to the tank.
I felt this design keeps the whole process very simple, it's easy to put a sponge in the bottom to keep things from clogging, initial setup is a BREEZE, simply dunk the whole unit into the water and tip to let the air out, tip it up right and remove from the water, voila, the siphon is primed and the unit is ready to roll!!
The only modifications I want to make to this is to the collection cup. I want to run it across the table saw a few times and give it some teeth (a dremel will work for this as well) and I also plan on grinding out a small ridge in the bottom of the female portion of the cup to allow the cup to slide easily up and down to adjust tank water level. Notice the built in Durso Stand pipe.. this unit functions nearly silently.
female to female joint (collection cup)
3" to 1-1/2" PVC
Adapter (bottom of collection cup)
1-1/2" to 1" pvc
Adapter (reduce bottom to 1" pipe... you could stay at 1-1/2" if you'd like, give a larger GPH
End cap (1)
1" barbed tubing connector
about 3' of 1" PVC
Pipe (lots of 2" pieces hehe)
 trying to re-upload images[/edit]