Filtreau Combi-NEXT Drum Filter with UVC – Gravity Fed with NEW XL Motor

Filtreau Combi-NEXT Drum Filter with UVC – Gravity Fed with NEW XL Motor

Automatic waste removal and moving-bed filtration for gravity-fed ponds

The Combi-NEXT Gravity is a combined drum and biological filter for a koi pond with bottom-drain or skimmer lines feeding the filter before the circulation pump. It provides automatic solids removal, a moving-bed section and 40W amalgam UV-C in a compact, full-height body.

Included media: this package comes with approximately 100 litres of moving-bed media. Allow for this included quantity before ordering any extra media; an appropriately sized external air pump is still required.

This is the version without an internal rinse pump. It is a sensible option when the cleaning-water arrangement is being specified separately; choose the Combi-NEXT with internal rinse pump if you want that pump built into the unit.

Waste removal and biological treatment

The 70-micron drum screen intercepts suspended solids before they reach the biological media. When restriction changes the water level, the controller operates the drum drive and rinse system, carrying collected dirt into the waste channel.

Behind that mechanical stage, moving media supplies surfaces for bacteria that process dissolved fish waste. Aeration both provides oxygen and keeps the media circulating. The 40W amalgam UV-C tackles suspended algae, which is a separate job from ammonia and nitrite conversion.

Planning the rinse-water supply

No internal wash pump is supplied with this version. A suitable external pressure-cleaning arrangement must therefore be part of the installation. If mains water is used, its controls and backflow protection need to be designed correctly; the filter should not simply be connected to an unprotected tap feed.

The drum motor, rinse pressure supply and pond circulation pump are three distinct components. The XL motor turns the drum, the rinse system cleans it, and the circulation pump moves water around the pond circuit. Buying one does not provide the functions of the others.

Media and air with room to move

Set the moving-bed loading around the actual chamber, retention fittings and delivered airflow. Allow for any media included in the selected package before ordering extras. The chamber needs open water and even circulation, not just the largest quantity of media that can be poured in.

A separate air pump supplies the fitted diffuser. Choose it for the water depth and media load, and keep fixed Japanese matting out of the moving section unless a separate static stage has been designed. Biological capacity develops as the media matures, so monitor ammonia and nitrite while increasing feeding.

A gravity-fed installation that works

Maximum flow is 30,000 litres/hour. Plan the three inlet branches and two outlets with accessible valves and enough pipe capacity to control draw-down. A pump that pulls water away faster than the pond lines can supply it will not improve filtration.

The 1,040 × 920 × 1,020 mm body needs a level base at the correct operating height. Compare the narrower Combi-AFTER Gravity if the filter area favours a longer body, or the pump-fed NEXT for a different water circuit.

Technical specification

Keeping maintenance straightforward

Retain space to inspect the drum, remove the UV assembly and reach the waste channel. Check the screen and spray pattern regularly, isolate power before servicing and do not let the cleaning pump run dry. Record the correct lamp and quartz references so routine replacement does not depend on a guess at wattage alone.

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