Insert filter with activated carbon for JBL internal filters from the CristalProfi i range.

Main Features:
• Clean and healthy water: The activated carbon insert prevents water discoloration and odors, and removes medicine residues.
• Usage: Simply place the filter cartridge in the filter container instead of the filter sponge.
• High-quality, water-neutral activated carbon that does not release phosphates into your aquarium water.
• It is renewed after about 2-3 weeks or as soon as the problem is resolved. It does not release the associated problematic substances back into the aquarium water.