DYMAX Slim Flo SF-500

Slim Hang-On-Back Filtration Without Taking Up Tank Space

The DYMAX Slim Flo SF-500 is a compact hang-on-back aquarium filter designed to provide effective filtration while keeping equipment out of the main aquarium display.

Instead of placing a bulky internal filter inside the tank, the Slim Flo hangs externally from the aquarium. This leaves more room inside for fish, plants and aquascaping while keeping the filter readily accessible for routine maintenance.

With approximately 470 L/h maximum flow, adjustable water output and a slim external design, the SF-500 is the largest model in the DYMAX Slim Flo range.

Why Choose the DYMAX Slim Flo SF-500?

• Slim hang-on-back aquarium filter

• Approximately 470 L/h maximum flow

• Adjustable flow rate

• Quiet operation

• Keeps the main filter body outside the aquarium

• Extendable intake tube

• Intake sponge included

• Easy access for cleaning and filter-media maintenance

• Supplied with filter media

• Replacement DYMAX cartridges available separately

• Suitable for planted and nano-style aquarium setups

More Space Inside Your Aquarium

One of the biggest advantages of a hang-on-back filter is simple: most of the filter stays outside the aquarium.

That means less equipment occupying valuable space inside your tank and fewer bulky components competing with the aquascape.

This can be particularly useful in planted and carefully aquascaped tanks, where keeping the display clean and uncluttered makes a noticeable difference.

The external position also makes the filter easier to access when it's time to inspect or maintain the filter media.

Adjustable Flow to Suit Your Aquarium

Not every aquarium needs the same amount of water movement.

The DYMAX Slim Flo SF-500 features adjustable flow, allowing you to reduce or increase the output to better suit the aquarium and its inhabitants.

This is useful for planted tanks and aquariums containing fish that don't appreciate excessively strong currents.

Rather than selecting flow based only on the filter's maximum rating, observe how water moves around your hardscape and plants and how your fish respond to the current. Adjust the SF-500 until you're achieving useful circulation without unnecessarily stressing the livestock.

Extendable Intake for Better Positioning

The SF-500 includes an extendable intake tube, allowing the intake strainer to be positioned further down into the aquarium where required.

This gives you more flexibility when setting the filter up on tanks with different water depths.

An included intake sponge also provides additional protection around the intake and is particularly useful in aquariums containing smaller livestock.

Cascading Return & Water Movement

Water returns to the aquarium through the Slim Flo's cascading outlet.

This creates surface movement as filtered water re-enters the aquarium, helping maintain circulation and gas exchange at the water surface.

Good surface movement is particularly useful because it helps prevent the surface from becoming stagnant while supporting oxygen exchange between the aquarium water and surrounding air.

Easy Filter Maintenance

A filter only works properly when it is maintained.

The Slim Flo's hang-on-back design keeps the filtration chamber readily accessible, making it straightforward to inspect and clean compared with equipment positioned deep inside an aquarium.

DYMAX also offers dedicated replacement cartridges for the SF-500. The DYMAX Slim Flo SFC-ML replacement cartridge is compatible with both the SF-240 and SF-500, making replacement media easy to source when required.

Avoid replacing or aggressively cleaning all established biological filter media at the same time, as beneficial bacteria living within the filtration system play an important role in aquarium stability.

What Comes With the DYMAX Slim Flo SF-500?

The manufacturer's listed inclusions are:

• DYMAX Slim Flo filter

• Intake tube

• Intake sponge

• Levelling knob

• Filter media

• Power cord

Replacement filter cartridges are available separately.

SF-500 Specifications

Model: DYMAX Slim Flo SF-500
Filter Type: External hang-on-back aquarium filter
Maximum Flow: Approximately 470 L/h (125 GPH manufacturer/distributor specification)
Flow Control: Adjustable
Aquarium Range: Manufacturer/distributor guidance approximately 38–91 L (10–24 US gallons)
Intake: Extendable intake tube with intake sponge
Replacement Cartridge: DYMAX Slim Flo Medium/Large cartridge (SF-240/SF-500)

Aquarium Haven Tip

Don't choose a filter based only on the maximum aquarium volume printed on the box.

Your stocking level, fish species, feeding, plants, hardscape and maintenance routine all influence how much filtration and circulation your aquarium actually needs.

Once the SF-500 is installed, check that you're getting good movement throughout the aquarium without creating an unnecessarily strong current. Use the adjustable flow to find the balance that suits your particular setup.