Nice start you have going there.
I'd like to throw in my 2 cents but please don't take it the wrong way I'm not trying to be rude.
These guys are giving you some valuable info and advice but you don't seem to keen to accept any of it, your plumbing is flawed and these guys are trying to help you along.
Last month I helped a local pet store setup their plubming and they were doing the same thing you are except only 7 1/2 feet of head and using the same pump. After I expressed my concern for the plan several times and they insited I went ahead and did what they ask, only to do it over when it didn't work. You could barley feel much flow threw the return.
That pump will be working overtime and you will be lucky to even get 500gph return.
Please listen to these guy most have more experience then you could shake a stick at. And Melev certainly has the experience and even quite a few tanks going.
And good luck I truely hope everything work out for you!
