HKM-238227 Activated Carbon Water Purification Cubes for Fish Tanks - Honeycomb Design, Various Sizes AvailableIntroducing the HKM 238227 Activated Carbon Water Purification Cubes for Fish Tanks, a reliable addition to your aquarium maintenance routine. These honeycomb designed carbon cubes are expertly crafted from high quality activated carbon, providing effective filtration that helps maintain the clarity and health of your water. Available in various sizes to good suit your needs, the HKM 238227 cubes come in both small and large options. The small size