i Have the side sponges all the way round on bottom shelf plastic balls then ceramic on next shelf . i do not put any fine filters in as this setup stays good for up to 6 weeks before clogging . I have seperate water polisher setup that is a filter on powerhead with filter pads that i change twice a week to keep water crystal clear FX5 s are nuts love it
One box of biomax per shelf. and the foam blocks. Works great. and doesn't effect flow that much b/c 500Grams of biomax isn't really to much but the surface area for BB is great when you add all 1500Grams.