Fluval SK400 Surface Skimmer

Keep your aquarium surface clean and improve water clarity with the Fluval SK400 Surface Skimmer. Designed for aquariums up to 400 L (105 US gal), the SK400 removes unwanted surface film and floating particles while helping improve oxygenation and light penetration.

Surface film can develop from fish food, dust, oils, household contaminants and other organic material. Besides affecting the appearance of your aquarium, a persistent surface film can interfere with gas exchange and reduce the amount of light reaching aquatic plants. The Fluval SK400 provides continuous powered surface skimming to help keep the water surface cleaner.

Powerful Aquarium Surface Skimming

Unlike a traditional aquarium filter that primarily draws water from below the surface, the Fluval SK400 Surface Skimmer is specifically designed to draw water from the surface where unwanted film accumulates.

The floating intake assembly automatically adjusts as the aquarium water level changes, helping maintain consistent surface skimming during normal evaporation and water-level fluctuations.

Key Features

• Designed for aquariums up to 400 L / 105 US gal
• Removes unwanted surface film and floating debris
• Helps improve oxygenation and light penetration
• Self-adjusting floating intake assembly
• Adjustable overall flow control
• Adjustable skimming intensity
• Fine filter sponge helps trap particles
• Output diffuser provides directional or multi-directional flow
• Suitable for both rimmed and rimless aquariums
• Compact design helps minimize obstruction inside the aquarium
• Modular construction makes cleaning and maintenance easier
• Energy-efficient North American model rated at 3.3 W

Why Use a Surface Skimmer?

A thin layer of film on the aquarium surface can make an otherwise clean aquarium look dull or cloudy. It can come from oils, dust, fish food and other materials that accumulate at the water’s surface.

The Fluval SK400 continuously skims the surface to help remove this unwanted buildup. By keeping the surface clearer, it can also help improve gas exchange and light penetration for planted aquariums.

Self-Leveling Floating Intake

One of the most useful features of the Fluval SK400 Surface Skimmer is its floating intake assembly.

The intake follows changes in the aquarium water level, helping it remain positioned at the surface where film accumulates. This means normal evaporation does not require constant manual adjustment of the skimmer position.

For best performance, Fluval recommends positioning the skimmer where there is relatively little water movement and adjusting the floating intake correctly above the skimmer body.

Adjustable Flow and Skimming Intensity

The SK400 gives you control over how aggressively it skims.

The flow control slider allows the overall water flow to be adjusted, while the intake regulator dial lets you adjust the skimming intensity. This makes it easier to adapt the skimmer to different aquarium sizes and livestock requirements.

The output diffuser can also be configured for unidirectional or multi-directional water flow.

Compact Design for Rimmed and Rimless Aquariums

The Fluval SK400 features a compact design that can be positioned inside the aquarium without significantly obstructing the viewing area.

Its rear spacer is designed to accommodate both rimmed and rimless aquariums, providing greater flexibility when positioning the unit.

Fine Filter Sponge

In addition to removing surface film, the SK400 includes a fine filter sponge that helps capture particles as water passes through the unit.

The modular design allows the components to be accessed and removed for routine cleaning and maintenance.

Is the Fluval SK400 a Replacement for Your Main Filter?

No. The SK400 is designed as a surface skimmer and should be used in addition to your aquarium’s primary filtration system, rather than as a replacement for a conventional aquarium filter. Fluval specifically recommends using it alongside traditional filtration.

This makes it particularly useful for aquariums where the main filter provides adequate water filtration but surface film remains a problem.

Fluval SK400 for Freshwater and Saltwater Aquariums

The Fluval SK400 can be used in both freshwater and saltwater aquariums. Fluval notes that surface skimmers can be particularly useful in marine aquariums that do not have an overflow system.

Always ensure the skimmer is installed and maintained according to the manufacturer’s instructions.

Fluval SK400 Maintenance

Regular maintenance helps keep the skimmer operating properly.

Fluval recommends cleaning the impeller monthly for optimal functionality and recommends annual impeller replacement. Components can also be soaked in a water-and-vinegar solution to help remove calcium buildup, followed by thorough rinsing with fresh water.

Before cleaning:

1. Unplug the SK400 from the power supply.
2. Remove the appropriate components.
3. Clean the filter sponge and skimmer parts.
4. Inspect and clean the impeller.
5. Remove calcium buildup if necessary.
6. Rinse all components thoroughly.
7. Reassemble and reinstall the skimmer.
8. Restore power and check operation.

Never submerge the electrical plug or power connection.

Fluval SK400 Surface Skimmer Canada

Looking for a Fluval SK400 Surface Skimmer in Canada? Canadian Aquarist offers aquarium filtration equipment and accessories for aquarists across Canada.

The SK400 is an excellent addition for aquariums where surface film, floating particles or reduced surface clarity are affecting the appearance of the tank.

With adjustable flow, a self-leveling intake and compact installation, the Fluval SK400 Surface Skimmer provides a practical way to keep the aquarium surface cleaner.

Frequently Asked Questions

What does the Fluval SK400 Surface Skimmer do?

The SK400 removes unwanted film and floating material from the aquarium’s water surface. It also helps improve oxygenation and light penetration.

What size aquarium is the Fluval SK400 suitable for?

The SK400 is designed for aquariums up to 400 litres (105 US gallons).

Does the Fluval SK400 replace an aquarium filter?

No. It is designed to be used in addition to a traditional aquarium filter, not as a replacement.

Can I use the Fluval SK400 in a saltwater aquarium?

Yes. Fluval states that the SK400 can be used in saltwater aquariums as well as freshwater setups.

Does the SK400 work with changing water levels?

Yes. Its floating intake assembly self-adjusts as the aquarium water level changes, helping maintain surface skimming during normal water-level fluctuations.

Can I adjust the flow of the SK400?

Yes. The SK400 includes a flow control slider and an intake regulator dial for adjusting overall flow and skimming intensity.

How often should I clean the Fluval SK400?

Regular maintenance is recommended. Fluval specifically recommends cleaning the impeller monthly to maintain optimal functionality.

Where can I buy the Fluval SK400 in Canada?

You can purchase the Fluval SK400 Surface Skimmer from Canadian Aquarist, with aquarium equipment and accessories available to aquarists across Canada.