I run 2 reflow super dart golds (4 returns to DT per) ....I have a manifold that has 4 outlets (gfo, carbon, ca reactor fed, and a spare, also have 2 1in manifolds...1 to fuge, and 1 that runs a 24in x 8in fluidized sand bed filter.....all of these manifolds though are run off the drains and strictly ran with gravity :spin1:......the drain system is pushing over 7000 gph threw the sump......only 4 pumps in the system the two return pumps and the 2 red dragons on my skimmer......oh and the system also has 300w of uv:spin3: