I have a 75gal that I picked up used with a Fluval G6, people either love or hate them from my reading, the clips that hold the mechanical filter broke and it did not make sense to by parts when I could get a new filter for same cost. But the filter has flow, temp, conductivity display which is cool.

Today I bought a Eheim pro4+ for $150 at petsmart to replace the G6, I have them both running right now to colonize bacteria on the new media. I got to thinking that maybe running them both would be a good idea. First reason is that I have water flow I been wanting. Second is well more filtration= cleaner water.

So now I am trying to figure out what media and how to place it. I'd like to keep the Eheim running as it is designed for a while till I have more experience with it. How could I best utilize the G6? Biological filtration would make the most sense but really there is nothing to gain there. The bacteria is only going to grow there is available food. My other thought is use it to polish water. Any suggestions on the media? Or other setups?