Fluval 204 - 304 / 205 - 305 Foam Filter Block 2 pieces per display pack Fluval Foam Inserts capture large particles for effective mechanical filtration, the crucial first stage in the filtration process. Custom fit to prevent bypass, they have a pore size that allows efficient water flow with less clogging for long-lasting filtration. These inserts also enhance biological filtration. For freshwater and marine environments.

Fluval 204 - 304 / 205 - 305 Foam Filter Block 2 pieces per display pack Fluval Foam Inserts capture large particles for effective mechanical filtration, the crucial first stage in the filtration process. Custom fit to prevent bypass, they have a pore size that allows efficient water flow with less clogging for long-lasting filtration. These inserts also enhance biological filtration. For freshwater and marine environments.