55 gal main tank, the overflow i'm looking at says 300gph, in to a 20gal sump, with a mag 5 return pump going up 4', in to 2...maybe 3 returns. Do you guys see any problems in this setup with either the overflow or the return pump? Will i be losing too much flow and should be looking at a mag 7 or something? Just checking to make sure everything is okay before finding out the hardway that one can't handle the other.