Fluval internal filters also known as underwater filters are designed for various underwater applications, internals can be used as a primary or supplemental filter and feature versatile mounting options.
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Fluval U1 Underwater Filter Description
Compact 3-Stage Filtration for Aquariums up to 55L
The Fluval U1 Underwater Filter offers efficient, versatile filtration in a compact design, ideal for aquariums up to 55 litres (15 US gallons). Part of the U Series, this filter provides reliable 3-stage filtration, enhancing water quality in freshwater, saltwater, and reptile environments.
Fluval U1 Underwater Filter Key Features
3-Stage Filtration: Offers mechanical, chemical, and biological filtration for clear, healthy water. The U1 model is perfect as a primary filter in smaller tanks or as a supplementary filter in larger setups.
Adjustable Flow Control: Features an adjustable flow control to customise water movement and increase aeration, ensuring optimal conditions for aquatic life.
Multiple Position Options: Install vertically to create currents or unique flow patterns, or position horizontally for use in shallow tanks, low-water setups, or to create a decorative waterfall effect.
Quick and Easy Maintenance: The convenient flip-top lid allows easy access to the filter cartridge, making maintenance or replacement quick and straightforward.
Compatible with Clean & Clear Cartridge: The Clean & Clear cartridge, packed with high-performance resins to reduce phosphate and nitrate, fits easily into the U1’s foam pad slot, helping prevent algae growth and maintaining water clarity.
Sleek, Space-Saving Design: Compact and stylish, the U1 is ideal for tanks where external filtration isn’t an option.
Made in Italy: Built with quality and durability, ensuring lasting performance in various aquatic environments.
Fluval U1 Underwater Filter Included Components
1 Foam Pad
Adjustable Flow Control
Flip-Top Lid for Easy Access
Fluval U1 Underwater Filter Suitable For
Aquariums up to 55L (15 US gallons)
Freshwater, saltwater, and reptile environments
Shallow tanks or setups with low water levels
Whether used as a primary filter in smaller tanks or a supplementary filter in larger aquariums, the Fluval U1 Underwater Filter provides reliable filtration and easy customisation to suit a range of aquatic environments.
Fluval U2 Underwater Filter Description
3-Stage Filtration for Aquariums up to 110L
The Fluval U2 Underwater Filter provides powerful, efficient 3-stage filtration, ideal for aquariums from 45 to 110 litres (12 to 30 US gallons). Part of the versatile U Series, the U2 filter combines mechanical, chemical, and biological filtration, making it suitable for freshwater, saltwater, and reptile environments.
Fluval U2 Underwater Filter Key Features
3-Stage Filtration: Offers complete filtration with foam pads for debris capture, Poly/Carbon cartridges for chemical filtration, and BIOMAX Biological Rings for biological filtration, ensuring clean and healthy water.
Adjustable 3-Way Flow Control: Choose between three output settings to suit your aquarium’s needs:
Top Output: For maximum circulation and oxygenation.
Integrated Spray Bar: Provides a gentle, even flow, ideal for planted aquariums.
Bottom Output: For deepwater agitation, enhancing circulation at lower levels.
Convenient Flip-Top Lid: Allows quick access to filter cartridges, making maintenance and replacements easy and efficient.
Installation Flexibility: Position vertically against the aquarium wall for customised currents, or place horizontally in shallow tanks to create decorative waterfall features.
Clean & Clear Compatibility: Compatible with Fluval’s Clean & Clear cartridge, which is designed to reduce phosphate and nitrate, prevent algae growth, and keep water crystal clear (sold separately).
Versatile Use: Ideal for smaller tanks as a primary filter or as a supplementary filter in larger setups.
Fluval U2 Underwater Filter What’s Included
2 Foam Pads
2 Poly/Carbon Cartridges
BIOMAX Biological Rings
Fluval U2 Underwater Filter Additional Features
Compact and Sleek Design: Fits seamlessly within your aquarium setup.
Made in Italy: Crafted with high-quality materials, suitable for freshwater, marine, and reptile environments.
Whether you need reliable filtration for a small tank or additional support in a larger setup, the Fluval U2 Underwater Filter delivers effective, versatile filtration to keep your aquarium clean and healthy.
Fluval U3 Underwater Filter Description
High-Performance 3-Stage Filtration for Aquariums up to 150L
The Fluval U3 Underwater Filter provides powerful 3-stage filtration, ideal for aquariums from 90 to 150 litres (24 to 40 US gallons). Part of Fluval’s U Series, the U3 filter ensures clean, healthy water quality for freshwater, marine, and reptile environments, with versatile options for customising flow and easy maintenance.
Fluval U3 Underwater Filter Key Features
Efficient 3-Stage Filtration: Offers complete mechanical, chemical, and biological filtration with dual foam pads for debris capture, Poly/Carbon cartridges for chemical purification, and BIOMAX Biological Rings for enhanced biological filtration.
Adjustable 3-Way Flow Control: Allows for custom water flow options to suit different aquarium needs:
Top Output: Provides maximum circulation and oxygenation for vibrant aquatic life.
Integrated Spray Bar: Delivers a gentle, even flow, ideal for planted aquariums.
Bottom Output: Agitates deep water, improving circulation at lower levels.
Convenient Flip-Top Lid: Easy access to filter cartridges for quick maintenance and replacement, ensuring hassle-free upkeep.
Flexible Installation Options: Can be installed vertically on the aquarium wall to create currents and unique flow patterns or positioned horizontally in shallow tanks to create decorative waterfall effects.
Clean & Clear Cartridge Compatible: Compatible with the optional Fluval Clean & Clear cartridge (sold separately), which helps reduce phosphate and nitrate levels, preventing algae growth and promoting water clarity.
Multi-Use Design: Suitable as a primary filter for medium-sized aquariums or a supplementary filter in larger setups.
Fluval U3 Underwater Filter What’s Included
2 Foam Pads
2 Poly/Carbon Cartridges
BIOMAX Biological Rings
Fluval U3 Underwater Filter Additional Features
Made in Italy: Engineered for durability and quality, suitable for freshwater, saltwater, and reptile environments.
Enhanced Aeration and Circulation: Increases water movement and oxygenation, supporting the health of your aquarium inhabitants.
The Fluval U3 Underwater Filter combines effective filtration with flexible installation options, making it a perfect solution for both beginner and experienced aquarium owners seeking reliable, efficient filtration.
Fluval U4 Underwater Filter Description
Advanced 3-Stage Filtration for Aquariums up to 240L
The Fluval U4 Underwater Filter offers high-performance 3-stage filtration in a versatile, compact design, ideal for aquariums from 130 to 240 litres (34 to 65 US gallons). Part of Fluval’s U Series, the U4 model ensures superior water quality with effective mechanical, chemical, and biological filtration suitable for freshwater, saltwater, and reptile environments.
Fluval U4 Underwater Filter Key Features:
Comprehensive 3-Stage Filtration: Equipped with foam pads for mechanical filtration, Poly/Carbon cartridges for chemical filtration, and BIOMAX Biological Rings for optimal biological filtration, keeping water clear and healthy.
Adjustable 3-Way Flow Control: Tailor water flow to suit your aquarium’s specific needs with three settings:
Top Output: Provides maximum circulation and oxygenation, ideal for enhancing water quality.
Integrated Spray Bar: Delivers a gentle, even flow, ideal for planted aquariums that require a balanced water flow.
Bottom Output: Creates deepwater agitation, promoting circulation at lower levels in the tank.
Flip-Top Lid for Easy Maintenance: Quick access to filter cartridges for efficient maintenance and replacement, saving time and effort.
Flexible Installation Options: Can be installed vertically on the aquarium wall to create currents and flow patterns or placed horizontally in shallow tanks for decorative waterfall effects.
Compatible with Clean & Clear Cartridge: Designed to work with Fluval’s Clean & Clear cartridge (sold separately), which helps reduce phosphate and nitrate levels, control algae, and maintain water clarity.
Versatile Usage: Ideal as a primary filter in medium-sized tanks or as a supplementary filter in larger aquariums where additional filtration is needed.
Fluval U4 Underwater Filter What’s Included:
2 Foam Pads
2 Poly/Carbon Cartridges
BIOMAX Biological Rings
Fluval U4 Underwater Filter Additional Features:
Made in Italy: Constructed with high-quality materials for reliable, durable performance.
Perfect for Various Environments: Suitable for freshwater, saltwater, and reptile habitats, supporting a wide range of aquatic needs.
Enhanced Aeration and Circulation: Increases water movement, providing essential aeration to promote a healthy ecosystem for your aquatic life.
The Fluval U4 Underwater Filter is a versatile, high-performance solution for aquarists seeking effective and customisable filtration, providing optimal water quality and ease of maintenance in a range of aquatic environments.
