As some of you may remember, when I set up my 150, my plan was to run 2 xp4's and an AC110. Well, I ended up with the tank too close to the wall and couldn't run the AC110. So, I ended up finding a good deal on craigslist. I bought an Fx5 and Xp4 both full of media, 2 400w Hydor heaters a powerhead, syphon hose, big nets and tons and tons of plants for $165! The worst part is that the lady gave away a 135g tank a few weeks ago! Anyway, I'm thinking of running the 2 xp4's for bio and the Fx5 for polishing and let my mom use the Xp4 on her 90g. Im gonna throw the boat load of ceramic rings that came in the Fx5 into the 2 Xp4's already on the 150 and just fill the Fx5 up with polishing pads. Just wondering if you all would think this would work.