Fluval U Series Underwater Filters (A460-A480) 3 Stage filtration with BIOMAX for superior aquarium water quality, flip top access for quick and easy cartridge replacement and three way flow control make the new Fluval U Series the benchmark in underwater filtration. Fluval underwater filters with three stage filtration are ideal for use in fresh, marine or reptile environments. Stage 1 foam removes large particles. Stage 2 poly/carbon cartridge traps fine debris, improves water clarity and removes impurities. Stage 3 BIOMAX provides optimal biological filtration efficiency. . For aquariums, terrariums and turtle tanks . Ideal supplemental or stand-alone filter, or for installations where external filtration is not possible . Filters debris and provides optimal biological filtration . Silent and efficient . Simple to install and maintain . Engineered and manufactured in Italy