Fluval SK400 Surface Skimmer – Up to 105 Gal, Adjustable Flow

Keep your tank clean, clear, and thriving

The Fluval SK400 Surface Skimmer is designed for aquariums up to 105 gallons (400 L). It targets the oily surface film that can form from dust, oils, and routine feeding, helping surface water feel more open and look more pristine. By reducing surface buildup, it supports healthier gas exchange and light access, which can matter for both fish comfort and plant vitality. This compact, energy-efficient device blends into any setup without overwhelming your view, offering real-world benefits you can notice over time.

How it works

The SK400 actively skims the upper water layer, pulling away surface contaminants before they spread deeper. A floating intake automatically adjusts with changing water levels, while an output diffuser distributes water flow in a controlled pattern. An adjustable flow slider and intake regulator let you tailor skimming intensity to suit your tank’s needs, whether you’re maintaining a planted freshwater setup or a mixed reef environment.

• Removes surface film from dust, oils, and food residues to improve water appearance and perceived clarity
• Enhances surface oxygen exchange and allows more light to reach aquatic plants and decorations
• Fine-tuned control with a flow slider and intake regulator for tanks up to 105 gallons (400 L)
• Floating intake automatically adapts to water level changes for consistent skimming performance
• Output diffuser enables customizable flow patterns to suit different aquariums
• Energy-efficient operation at 3.3W with a fine filter sponge for debris capture
• Modular design allows quick cleaning and easy access to parts for maintenance

Practical benefits for your tank

In everyday use, you’ll notice a cleaner surface and clearer water, with improved light penetration for plant growth and a more inviting viewing experience. The SK400’s compact form fits both rimmed and rimless tanks, so you can install it with minimal disruption. Its energy-efficient profile makes it suitable for continuous use, while the modular construction simplifies routine maintenance and part replacement. While not a guarantee, these design choices work together to support a tidy, well-functioning aquarium environment across freshwater and saltwater setups.

• Compact, unobtrusive design that blends with rimmed or rimless tanks
• Easy installation and straightforward maintenance for busy hobbyists
• Suitable for both freshwater and saltwater environments
• Quiet operation with energy-conscious performance

Overall, the Fluval SK400 offers precise control and practical features that help keep surface conditions favorable for observing your aquatic life and enjoying a clear, bright tank.