now that i have upgraded my lighting systems to MHs....the canopy wouldnt fit into the tank with the HOB filters...so if id rip those off...i would lose about...1000gph...of flow...i was thinking about getting 2 seios...about 800 gph each and shoot them on opposite ends....as for my filtration goes....i have the sump...would that be enough to keep my tank clean? ohh yeh i also have about 80-100 lbs of LR....in the 75G tank....