Right now I have a Mag 7 in my sump returning to main tank. Now that is 700 gph @ 0 feet but @ 4 feet that 400 gph not good for a 135 gal tank right. Now if some one can tell me the best flow rate for 135 gal tanks that would be helpful i look at the Aqua Sea AMP Master 2100 now is that enough flow for my 135. I am doing this because my hang on overflows stop shiponing all the time and i think it is because the return pump is not pushing enough flow through the tank for the overflow correctly is true or do hang-on over flow just suck. 



