Fluval U series filters provide the option of setting the flow output in 3 different positions, a key benchmark in underwater filtration. The Adjustable 3-Way Flow Control feature (U2, U3 and U4 models) lets you position the water flow output to meet your specific needs. The Top Output setting provides maximum circulation and oxygenation, the Integrated Spray Bar setting provides a gentle, even flow for planted aquariums, and the Bottom Output setting is for deepwater agitation. Fluval U Filters also include a convenient flip-top lid that allows quick and easy access to the filter cartridge for maintenance or replacement. In addition, Fluval U Filters offer installation versatility: they can be installed vertically against the aquarium wall to create currents or customized flow patterns; or they can be placed horizontally in shallow water tanks or to create decorative features such as waterfalls. Learn More

Fluval Poly/Carbon Cartridges features two sides for effective chemical filtration, the crucial second stage in the filtration process. The polyester filter pad side filters out fine debris and contaminants. The Carbon side filters out harmful liquid substances, colorants and odors. For freshwater, marine or reptile environments. For U series filter model: U3 Learn More

Fluval Poly/Carbon Cartridges features two sides for effective chemical filtration, the crucial second stage in the filtration process. The polyester filter pad side filters out fine debris and contaminants. The Carbon side filters out harmful liquid substances, colorants and odors. For freshwater, marine or reptile environments. For U series filter model: U3 Learn More

Fluval BIOMAX provides an optimal environment for beneficial bacteria growth. The bio rings have a complex pore system creating an optimal environment where beneficial bacteria can thrive. It also reduces and controls ammonia and nitrate. For freshwater and marine environments.For U series filter models: U2,U3,U4 Learn More

Fluval Poly/Clearmax filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate. It effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants. The filter cartridge helps reduce overall aquarium maintenance. It is ideal for freshwater and marine environments and designed for Fluval's U2 Underwater Filter. Contains 2 cartridges Key Features - Filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate - Effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants - Helps reduce overall aquarium maintenance - Ideal for freshwater and marine environments - Designed for Fluval's U3 Underwater Filter - Each box contains 2 cartridges Learn More

Fluval Poly/Clearmax filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate. It effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants. The filter cartridge helps reduce overall aquarium maintenance. It is ideal for freshwater and marine environments and designed for Fluval's U2 Underwater Filter. Contains 2 cartridges Key Features - Filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate - Effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants - Helps reduce overall aquarium maintenance - Ideal for freshwater and marine environments - Designed for Fluval's U3 Underwater Filter - Each box contains 2 cartridges Learn More

Fluval Poly/Clearmax filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate. It effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants. The filter cartridge helps reduce overall aquarium maintenance. It is ideal for freshwater and marine environments and designed for Fluval's U2 Underwater Filter. Contains 2 cartridges Key Features - Filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate - Effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants - Helps reduce overall aquarium maintenance - Ideal for freshwater and marine environments - Designed for Fluval's U3 Underwater Filter - Each box contains 2 cartridges Learn More

Fluval BIOMAX provides an optimal environment for beneficial bacteria growth. The bio rings have a complex pore system creating an optimal environment where beneficial bacteria can thrive. It also reduces and controls ammonia and nitrate. For freshwater and marine environments.For U series filter models: U2,U3,U4 Learn More

Fluval Poly/Carbon Cartridges features two sides for effective chemical filtration, the crucial second stage in the filtration process. The polyester filter pad side filters out fine debris and contaminants. The Carbon side filters out harmful liquid substances, colorants and odors. For freshwater, marine or reptile environments. For U series filter model: U3 Learn More

Fluval Foam pads capture large particles and debris 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. For freshwater, marine or reptile environments. For U series filter model: U3 Learn More

Fluval Poly/Clearmax filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate. It effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants. The filter cartridge helps reduce overall aquarium maintenance. It is ideal for freshwater and marine environments and designed for Fluval's U2 Underwater Filter. Contains 2 cartridges Key Features - Filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate - Effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants - Helps reduce overall aquarium maintenance - Ideal for freshwater and marine environments - Designed for Fluval's U3 Underwater Filter - Each box contains 2 cartridges Learn More

Fluval Poly/Clearmax filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate. It effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants. The filter cartridge helps reduce overall aquarium maintenance. It is ideal for freshwater and marine environments and designed for Fluval's U2 Underwater Filter. Contains 2 cartridges Key Features - Filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate - Effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants - Helps reduce overall aquarium maintenance - Ideal for freshwater and marine environments - Designed for Fluval's U3 Underwater Filter - Each box contains 2 cartridges Learn More

Fluval BIOMAX provides an optimal environment for beneficial bacteria growth. The bio rings have a complex pore system creating an optimal environment where beneficial bacteria can thrive. It also reduces and controls ammonia and nitrate. For freshwater and marine environments.For U series filter models: U2,U3,U4 Learn More

Fluval Foam pads capture large particles and debris 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. For freshwater, marine or reptile environments. For U series filter model: U3 Learn More