Bio-Foam+ Foam Blocks for Fluval FX4/FX5/FX6 Filters, 2-Pack

Specially designed for Fluval FX4, FX5 and FX6 high-performance external filters, Bio-Foam + foam blocks work extra hard by acting as an effective filter medium for both mechanical and biological filtration.

Key Features:

• Provide mechanical and biological filtration;
• Include a large porous surface area that supports the expansive proliferation of beneficial (nitrifying) bacteria;
• Effectively trap small particles and debris, especially those not retained by the foam during the first filtration stage;
• Are custom-fitted specifically for FX series filters to increase filtration efficiency;
• Help create a healthy aquatic environment and ideal water conditions;
• Should be rinsed every 3 months;
• Should be replaced every 6 months;
• Are available in a convenient pack of 2;
• Are suitable for both freshwater and saltwater aquariums.