Fluval Foam Filter Blocks

Split for convenience, come packaged for each size fluval filter. The construction of the foam inserts allows plentiful bacterial populations for biological action. Abundant pores in the foam provide multiple attachment points for bacteria. Porous construction also enhances mechanical removal of smaller wastes missed by lower modules. The numerous pathways that the water is forced to travel as it flows through the block also increases the filtering efficiency. The actual area the water must travel through can be greater than ten times the measurable volume of the foam block. Although not permanent, the sponge inserts can be rinsed and reused a number of times before replacement.