FilStar Media

I've got coarse and fine sponges (came with the filter), bio-max (Aquaclear media, the store was out of FilStar bio-stars) and floss. It seems to work pretty well - the sponges do a great job of mechanical filtration, and the floss catches the fine bits that get through.
 
For my xp3's, in the bottom basket I use two Foam 30's / two Foam 20's. The middle basket is filled with Big Al's filter floss. The top basket I use bio chem stars and ceramic rings / and another Foam 30.

In my XP2's, In the bottom basket I use two Foam 30's / two Foam 20's. The top basket is filled with Big Al's filter floss.

In my Xp1, I use a Foam 30, a Foam 20, and some BA's Filter Floss.
 
Bottom basket has Eheim Ceramic Noodles (Efhimech), middle has the coarse and fine foams (30/20), and top has bioballs. I ocassionally throw in some fine filter floss over the bioballs.
 
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