The Fluval U4 Internal Filter provides powerful 3-stage filtration, increased water movement, and essential aeration for aquariums up to 240 litres. With its improved design, versatile positioning, and easy maintenance features, it is ideal for both freshwater and saltwater setups, as well as reptile environments.

Key Features:

• 3-stage filtration: mechanical, chemical, and biological
• Sleek design with easy-grip water control paddle
• Redesigned media cartridge for improved debris capture
• Suitable for aquariums 130–240L (34–65 US gal)
• Flip-top lid for quick cartridge access and maintenance
• Adjustable 3-way flow control: top output, spray bar, or bottom output
• Can be positioned vertically or horizontally
• Includes BioMax biological media
• Output: 1000 L/h (260 US gal)
• Dimensions: 11 x 10 x 33cm
• Energy efficient: 10–12W power consumption
• Made in Italy

Whether used as a main filter for mid-sized aquariums or a supplementary filter for larger systems, the Fluval U4 delivers strong performance, reliability, and flexibility. Its versatile setup options and quiet operation make it a trusted choice for aquarists.

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We really want you to be happy with the product that you've received. If however, when the goods arrive they're not what you want, then no problem - we have a 60 day no quibble return guarantee. Just let us know that you're going to return the item(s) by contacting us(stating your Order Number) and complete the returns packing slip that will have been included with your delivery. This will help us to quickly identify the item that you have returned (unopened and unused) - and we'll put a refund through for you.