3 in 1 filter: a filter with an aquarium pump and a double filter, it filters the water while adding oxygen and creating a fountain that helps agitate the water and improve ventilation . Dual Filtration System: Activated carbon and foam form the best water filtration system for small aquariums (sold separately), ensuring good oxygenation for clear water and a healthy environment. EASY TO USE: Quick to assemble and disassemble, and comes with five suction cups for safe installation in the aquarium Humanized design: the water inlet adopts a narrow fence, which can effectively prevent fish and shrimp from entering the filter Wide range of use: ideal for irregularly shaped or shallow water habitats - can be mounted horizontally or vertically and can be fully submerged.