Brian- What Im doing with my two ro's is working for now. Im just thinking of playing around and trying to soup them up on the cheap. If I found a couple high pressure pumps, even piston ones, and added them to each machine I would have honest 1200's like yours. Then Im going to hook them together so I can run them independently or together where all the flows would go through all four membranes. Then Id have pretty much an honest 2400 rig. I would be able to single pass stuff after very little recirc real high. Thats what Im thinking. I priced a 4 post machine new like what Im describing and theyre 50 some thousand. Im going to keep working on my garage sale equipment and not spend the money. Im tired of paying back stuff. If I had unlimited money Id buy a new one becouse it really would be great but I dont so Im going to keep doing stuff the way Im doing it and just keep trying to make things better on my own. Theron