Filtreau Excellent Mountain Tree Combi Drum 50/65 XL – Gravity Fed

Filtreau Excellent Mountain Tree Combi Drum 50/65 XL – Gravity Fed

A long-format combi with specialist rotating biological media

The Excellent Mountain Tree 50/65 XL is a long-format gravity-fed combi with a larger mechanical drum and a specialist rotating biological stage. It is designed for a pond system needing substantial circulation without moving to the broadest Mountain Tree housing.

Its body is 2,370 mm long and 790 mm wide, with a height of 1,005 mm. The 650 mm-diameter mechanical drum provides a different scale of solids removal from the smaller low-profile Mountain Tree models.

Mechanical cleaning before the specialist media

The 120-micron screen separates suspended waste. Loading changes the water level and triggers automatic rinsing, with the internal wash pump feeding the spray bar while the drum rotates. Dirt leaves through the waste channel rather than building up around the biological media.

The rotating biological arrangement uses Mountain Tree Lotus Root Bacteria House media and Spiral Filter Mat. Its separate drive and purpose-built media layout are what distinguish this model from a conventional combi with a loose moving bed.

Why the media selection is different

The specialist media provides surfaces for biological colonisation in the intended rotating arrangement. Preserve that arrangement when maintaining or replacing media, and do not add a standard Hel-X-and-Japanese-matting bundle without checking the exact component layout.

An external air pump must supply the fitted air bars at their working depth. The biological stage needs oxygen and time to mature, so start with controlled feeding and check ammonia and nitrite as demand increases. Avoid treating the size of the media surfaces as a guarantee that any fish load will be safe.

Flow, connections and UV

The maximum gravity-fed flow is 65,000 litres/hour. Seven 110 mm inlets and three outlets need a balanced pipe arrangement, with accessible isolation valves and enough capacity to keep draw-down under control. The pump setting should follow the capability of the complete circuit.

The included 80W high-output UV-C helps deal with suspended algae. It is a separate treatment from the media’s biological work, and it needs the correct HO lamp and quartz when serviced. Leave space to remove those components without disturbing the surrounding manifold.

Model specification

A filter-room layout you can maintain

Plan access along the full body, including both drive systems and the biological assembly. Support the base evenly and set the operating level correctly. Automated rinsing does not remove the need to inspect the waste channel, spray nozzles and screen.

Compare the 30/40 Low Mountain Tree where height is restricted, or the 80/100 XXL Mountain Tree for the larger broad-body layout. The conventional 50/65 Inline XL is a different media approach and may suit a project that favours separately selected Hel-X and static matting.

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