Fluval FX4 High-Performance Canister Filter for Aquariums Up to 250 Gal

Meet the Fluval FX4, a high‑performance canister filter designed to simplify maintenance and keep large freshwater or saltwater tanks pristine. Built with a compact footprint and robust filtration, this unit blends powerful water movement with precise media control to support healthier, clearer aquariums without demanding constant attention.

Powerful flow with smart filtration

• Pumps out up to 700 US gallons (2,650 L) of water per hour and provides about 450 GPH of circulating flow for steady turnover.
• Smart Pump Technology uses an electronic microchip to continuously monitor and optimize pump performance for efficiency and reliability.
• Self-starting design means setup is quick: just add water and plug in, with automatic air evacuation to maintain flow.

Multistage filtration you can customize

• Removable, stackable media baskets hold a total of 1 US gallon (3.9 L) of mechanical, chemical, and biological media, all included.
• Precision basket design minimizes water bypass and ensures media is seated for consistent filtration across layers.
• Each basket includes foam inserts for initial mechanical filtration, helping to trap debris before it reaches the media deeper in the system.

Maintenance made simple

• Instant-release T-handles enable quick lifting and separation of baskets for routine service.
• Air is automatically evacuated every 12 hours, supporting efficient filtration and reducing time spent on priming.

Compact, versatile design

At 16.5 inches tall, the FX4 is designed to fit under most aquariums while delivering substantial filtration for tanks up to 250 gallons. Its quiet operation and streamlined footprint help keep cabinet spaces tidy, making it a practical choice for larger setups that demand reliability.

Why choose Fluval FX4

Fluval has a long-standing history in aquarium filtration, combining innovative engineering with practical features that aquarists trust. The FX4 blends dependable hardware with thoughtful design, aiming to deliver clear water, stable circulation, and accessible maintenance for hobbyists at various skill levels.

Note: While the FX4 offers strong filtration potential, real-world results depend on tank size, stocking, feeding, and regular maintenance. The features described are capabilities to support filtration and ease of use, not guarantees of specific outcomes.