Review on 🐠 Ceramic Filter Rings for Aquarium Filtration - 140 Count - Compatible with C-Series and Magniflow Filters (PA11484) by Jamie Rios

Have used them in the past on other aquariums with great success and bought them again for a new canister filter. Just put them in one of the trays and leave them alone. I put them after the foam filters so they don't get too dirty and before the purigen. If necessary, simply rinse them with some aquarium water (do not rinse with rinse water or you will destroy your biological filter!) so that you can restore your biological filter without damaging or recycling it. This latest pack appears to have more pieces glued together than in the past. You can't separate them without breaking them. I'm not sure if that's really a problem. . . The reduction in surface area is minimal, but if you had a small area to fill with them, maybe it could take up more space? Great option as a biobed for your good bacteria!