I bought a used hang-on ecosystem 60 about two weeks ago. It came with a maxi jet 900 power head as a pump. After some research I discovered that this filter works best if 600-1000 gph are going through it. The maxi jet is only 250 gph. The pump area is only the exact size of the maxi jet. What pump would you recommend I use to get to the gph I need to be at? Thank you for your help!!