EFFECTIVE solution for internal overflow box??

[kumanan]

See that white thing on the top left corner... it acts like an overflow, skimming the top, just like a big acrylic box would. Im in the process of building an internal overflow, but I think this will do the trick just fine.

What are your guys inputs on this method? What rate do you think it will skim at with 1.5 inch pipping? seems like a great idea. Plus you save about $80 on an overflow box by just using the piping in this pic...

 

[chucksta1]

It'll skim at the rate of the return pump's uplift... up to a certain point ( 600 GPH guestimate!) after that, it would depend on what's un the other side of the wall.. How far does it drop, how many bends, etc.

The farther the drop, the harder it will suck.

 

[chucksta1]

Also, there's a reason an overflow box has it's "teeth" or edge covering a certain area. It has to do with pulling as much as possible from the surface of the watter. If I see the picture correctly, the majority of the water is coming from more than 1/4 inch below the surface. That means that it's skimming some from the watre's surface, but mostly from below it.

 

[kumanan]

well of course when I have it setup its going to be sticking out just like an acrylic box would.... the teeth would be doing the same job.

I just spoke to a custom builder of acrylic boxes and he told me the flaw of this pvc method is....
"1. The interior volume of the elbow will cause the bulkhead to become
completely submerged. This in turn causes the flow rate to increase
(siphoning). The elbow then drains, breaks the siphon, and sounds like a
toilet flushing. This cycle continues endlessly. You could put a piece of
tubing into the elbow to prevent siphoning, and if tuned correctly will
work. With a hole as far down as yours, you would probably need to add an
extension pipe to the elbow as well. If you are running a very small flow
rate (less than 900 gph for 1.5" bulkhead) the problem will be reduced or
eliminated."