Filtreau Combi 50XL Drum Filter with Built-in Rinse Pump – Gravity Fed

Filtreau Combi 50XL Drum Filter with Built-in Rinse Pump – Gravity Fed

A larger gravity-fed combi with twin UV-C units

The Filtreau Combi 50XL Gravity brings a larger drum and twin UV-C units to a combined mechanical and biological filtration system. It is intended for a pond where bottom-drain and skimmer lines deliver water to the filter before the circulation pumps.

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

The name is 50XL, but the maximum water flow for this gravity-fed version is 40,000 litres/hour. Choosing from the actual operating specification matters more than using the model name as a pump-sizing rule.

A larger mechanical stage with automatic washing

The drum is 520 mm in diameter and 420 mm long, with a 120-micron screen. Suspended solids collect on the mesh until the level sensor starts a rinse. The internal cleaning pump supplies the spray bar while the motor rotates the drum, carrying removed dirt through the waste channel.

Four 110 mm inlets give scope for separate drain and skimmer branches, while three outlets connect to the clean side of the system. Design those branches so their resistance and valve positions do not compromise the intended flow.

Twin amalgam UV-C and biological filtration

Two 40W amalgam UV-C units help control suspended algae. They need access for lamp and quartz servicing, and the correct replacement parts should be identified individually. Two lamps are not a substitute for a mature biological section.

Choose compatible moving-bed media and leave enough water space for it to circulate. The fitted diffuser requires a separate air pump with useful output at chamber depth. Account for any media supplied with the selected package before choosing an additional quantity.

Avoid converting the moving-media space into a packed static bed by adding matting without a separate compartment. The biological setup needs oxygen and even movement, with feeding increased gradually as the media establishes.

A complete system rather than a filter rating

The maximum koi-pond rating is 40,000 litres, while the general-pond figure is higher. Heavily stocked koi ponds need more margin than lightly stocked water features of the same volume. Consider the feeding load, mature media, oxygen supply and real circulation together.

The pump-fed 50XL receives water under pump pressure and has a different maximum flow. For a larger gravity-fed Excellent layout, compare the Excellent Combi 30/50, taking account of its different housing, UV and media arrangement.

Dimensions and connections

Planning access from the beginning

The 1,270 × 900 × 1,030 mm body needs a level, fully supported base at the correct operating height. Leave room to remove both UV assemblies and inspect the drum and waste route. Keep isolation valves within reach after the full manifold is installed.

Observe water levels and waste discharge during commissioning. Routine checks of the mesh, nozzles and drainage remain necessary, with power isolated before servicing. A change in cleaning frequency should prompt inspection of loading and restrictions, not just a controller adjustment.

Related equipment and advice

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• View the full Filtreau range
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• Read our drum filter guide
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• Choose a variable pond pump
• Choose a Charles Austen air pump
• Pressure pipe, valves and fittings
• View Filtreau UV-C units
• Find replacement UV lamps and quartz sleeves