i was up at petsmart looking for the ceramic rings and they have these things called bio-chem stars does anyone use these or are they just crap their trying to sell....cause it says to use the rings and like half a tray of the stars and the rings are kinda pricey like 17 bucks on big alls for a liter .....so i can only imagine the mark up from a lfs if i can find one that sells the brand