Filtreau Excellent Combi Drum 25/30 Low Version – Gravity Fed Inline

Filtreau Excellent Combi Drum 25/30 Low Version – Gravity Fed Inline

A low inline layout for gravity-fed koi pond filtration

The Excellent 25/30 Low Inline Gravity puts its treatment stages along a longer, narrower body. At 590 mm wide, it is a particularly useful comparison when a conventional combi is too wide for the planned filter area. The length is 1,935 mm, so the space saving is across the width rather than in every direction.

The layout brings together automatic drum cleaning, biological chambers and 80W high-output UV-C. It is built for a gravity-fed circuit: bottom-drain and skimmer water reaches the filter before the circulation pump, with the body installed at the correct pond operating level.

A slim layout with a proper cleaning system

The drum separates suspended dirt through a 120-micron screen. Its level-operated controller turns the drum and starts the internal wash pump when cleaning is needed. The spray bar removes trapped solids into the waste channel, leaving the biological sections a cleaner water supply.

Narrow does not mean that the filter can be boxed in tightly. Leave room along the body to open the lid, service the UV and reach the media. Position valves where they remain accessible after the return pipework has been fitted.

Matching the chambers with the media

The optional media setup pairs 100 litres of Hel-X with 2 m² of matting. Hel-X belongs in the aerated moving section; matting provides a separate fixed-media stage. The media and air pump are separate choices, and neither a full chamber nor a large nominal air-pump output guarantees the right movement at operating depth.

For loose matting, we offer our high-quality Japanese matting in 1.2 × 1 m sheets. Two sheets give 2.4 m² before cutting, but are supplied uncut rather than as a shaped cartridge. Plan the panel arrangement, clear water passages and removal space before trimming them. A compatible 25/30 Low Inline trickle stage can be considered separately if further biological treatment is wanted.

Understanding the flow figure

Maximum flow is 30,000 litres/hour. The three 110 mm inlet branches need pipework that can deliver the intended flow without excessive draw-down as the screen loads. Set a variable circulation pump to the performance of the whole circuit rather than running it flat out simply because it can.

The conventional 25/30 Low Gravity is shorter but wider, while the 30/40 Low Inline Gravity gives a larger drum in a slightly wider body. Those are useful practical comparisons before committing the filter pit dimensions.

Technical specification

Commissioning and access

Support the full base on a level surface and set the filter to its operating-level marking. A 750 mm body does not change that relationship with the pond. Arrange a clear waste discharge and accessible electrical isolation.

After filling, check levels and drainage through several rinse cycles. Biological media will take time to mature, so test ammonia and nitrite as feeding rises. Refer to the Excellent manual for maintenance, and inspect the screen and waste channel rather than assuming automatic means unattended.

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