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.