Manufactured exclusively for Hagen's Fluval FX4, FX5, and FX6 Filtration Systems, these foam blocks perform mechanical filtration, the crucial first stage in the filtration process.  These foam filter pads capture large particles and are custom fit to prevent bypass.  They enhance biological filtration, and are ideal for freshwater and marine aquariums.  For use with the Fluval FX4, FX5 and FX6 External Canister Filters.

Features:

• Performs mechanical filtration
• Traps Particles & Debris
• Enhances biological filtration
• Good for freshwater & marine environments
• Provides efficient water flow with less clogging for long lasting filtration
• Bulk packaged to save the environment
• SATISFACTION GUARANTEED!