Tetra Whisper Bio Foam Grid replacement kit. Bio Foam provides an extreme amount of surface area for optimal biological filtration in the Tetra In Tank Whisper power filters. The Bio-Foam Grid fits the Whisper In-Tank Power Filter. Each Whisper Bio Foam Kit includes foam and a plastic frame. For best results, replace the Bio Foam Grid according to the manufacturers recommended maintenance schedule.
BioFoam and Grid - PF 20i/40i (In tank)