I have a standard 100gal, my return pump is a mag 18 ran through 2 3/4 sea swirls, right now I have 2 Hydor Koralia Evolution Circulation 1400 Pumps on a wave maker that make the clicking sound that is driving me nuts. So they have to go. I am trying to figure out my next buy. I know that I want to go with Vortech, but which one is the question. I plaining on putting them on the back wall, so I am thinking that the MP40 would be too much, so I am leaning towards the MP10. I would like others thoughts thanks.