Filtreau Combi-AFTER Drum Filter with UVC – Gravity Fed

Filtreau Combi-AFTER Drum Filter with UVC Gravity Fed

Includes 100 Litres of Moving-Bed Media – Exclusive Upgrade

For a limited time, we are including approximately 100 litres of moving-bed media with the Filtreau Combi-AFTER Gravity at no additional cost. As a result, the system delivers greater biological capacity from day one, allowing the filter to stabilise more quickly and handle higher feeding levels with confidence.

The Filtreau Combi-AFTER Gravity is a professional-grade post-filtration drum system designed specifically for gravity-fed koi ponds and ornamental ponds up to 60m³, depending on stocking density. Unlike a primary drum unit, this model installs after an existing mechanical drum or sieve filter. Therefore, it acts as a dedicated polishing and biological stage, significantly improving overall water clarity and long-term stability.

Thanks to its slim 570mm profile, this model fits comfortably into narrower filter pits where space is limited. Despite its compact footprint, it houses a substantial 350 litre moving-bed biological chamber. Consequently, it provides serious nitrification performance and supports heavily stocked koi systems with ease. We recomend the Charles Austen ET100 Airpump for this filter.

In addition, the integrated 40W High Output UV-C immersion module operates at 253.7nm to suppress algae spores, bacteria and harmful microorganisms as water flows through the chamber. This not only improves clarity but also helps maintain healthier water conditions throughout the year.

Gravity Operation and Cleaning System

This gravity-fed version connects directly to a mains water supply for drum cleaning. Unlike the pump-assisted variant, it does not include an internal rinse pump. Instead, the system relies on mains pressure to power the automatic cleaning cycle.

When debris restricts flow through the drum screen, the stainless steel float switch detects the level change and immediately activates the cleaning cycle. The drum rotates while spray nozzles flush waste to drain using mains pressure, ensuring consistent and reliable self-cleaning performance.

However, if you require a model with an integrated wash pump, the alternative FS421INT version includes a built-in 5 bar rinse pump. Therefore, you can select the configuration that best suits your installation requirements. Or it can be purchased as an addon.

By using mains pressure on this version, the design reduces internal components and simplifies long-term servicing. As a result, it maintains dependable automated cleaning performance while keeping the system straightforward and robust.

Key Features

• Gravity-fed post-filter drum system
• Includes approximately 100 litres of moving-bed media
• Large 350 litre moving-bed biological chamber
• Slim 570mm wide footprint
• Integrated High Output UV-C unit
• Mains-fed automatic drum cleaning
• Stainless steel float-triggered rinse cycle
• Designed for installation after mechanical pre-filtration
• Suitable for koi ponds up to 60m³
• Maximum flow rate 30m³ per hour

Technical Specifications

• Model: Filtreau Combi-AFTER incl. UVC (Gravity)
• Item Number: COM0003
• Manufacturer SKU: FS421
• Installation: Gravity-fed post-filter
• Maximum Pond Volume: Up to 60m³
• Maximum Flow Rate: 30m³ per hour
• Dimensions:
• Length 1730mm
• Width 570mm
• Height 1020mm
• Inlets: 3 x 110mm
• Outlets: 3 x 110mm
• Biological Capacity: 350 litre moving-bed chamber
• Media Included: Approx. 100 litres moving-bed media
• UV-C: High Output 40w immersion module
• Cleaning System: Mains-fed automatic rinse system
• Control Box: Included