Burtons BD 300 Combi MK3 Pond Drum Filter

Burtons BD 300 Combi MK3 Pond Drum Filter

High Performance Self Cleaning Drum Filter with 150L Bio Chamber and Free Media Included

The Burtons BD 300 Combi MK3 Pond Drum Filter is the latest evolution of one of the most popular combi drum filters in the Burtons Aquatics range. Designed and manufactured in the UK, this advanced filtration system combines automatic drum filtration with a large integrated biological chamber to provide complete pond filtration in a single unit.

The 2026 MK3 version introduces several improvements over previous versions, most notably a larger 150 litre biological chamber, increased outlet flexibility and an upgraded control system with integrated socket panel. By combining powerful mechanical filtration with efficient biological filtration, the Burtons BD-300 Combi MK3 provides a reliable filtration solution for koi ponds up to approximately 35,000 litres depending on stocking levels.

The filter uses a precision 60 micron stainless steel drum screen to capture fine debris before it can break down in the pond. As a result, solid waste is removed before reaching the biological chamber, helping maintain stable water quality and crystal clear pond water.

When debris accumulates on the screen, an internal sensor automatically triggers the cleaning cycle. During this cycle the drum rotates while spray jets wash the screen clean and flush waste out to drain. Because the cleaning process is fully automatic, the filter continues operating efficiently without requiring manual cleaning.

Supplied With 150 Litres of Free Biological Media

One major advantage of purchasing the Burtons BD 300 Combi MK3 from us is that we supply the filter with 150 litres of biological media included free of charge. Many retailers sell combi drum filters without biological media. This means pond owners must purchase expensive moving bed media separately before the filter can operate properly.

However, we supply the BD 300 Combi MK3 ready to run with 150 litres of media included. This provides better value and allows beneficial bacteria to begin colonising the bio chamber immediately. As a result, the filtration system can establish more quickly and stabilise pond water sooner.

Upgraded MK3 Biological Filtration Chamber

One of the most important improvements in the MK3 version is the expanded biological chamber.

Earlier versions of the BD-300 Combi included a 100 litre bio chamber. The MK3 increases this capacity to 150 litres of moving bed media, significantly increasing the surface area available for beneficial bacteria. 50L of Burtons Bio Tube Media and 100L of Burtons Bio Flo+ Media

Moving bed filtration works by constantly circulating media inside the chamber. This movement allows bacteria to colonise the media while maintaining high oxygen levels. These beneficial bacteria convert harmful ammonia and nitrite into nitrate, helping maintain a healthy pond environment for koi. The increased media capacity allows the filter to handle higher stocking levels and improves overall filtration stability.

High Performance Drum Filtration

The BD 300 Combi MK3 uses a 60 micron stainless steel drum screen to remove fine debris from the pond water. Water enters the drum filter through three 110 mm inlet connections before passing through the rotating drum screen.

The screen captures debris such as:

• fish waste
• uneaten food
• blanketweed fragments
• suspended organic waste

As debris accumulates on the screen, the water level inside the drum chamber rises slightly. The internal sensor detects this change and activates the cleaning cycle. During the cleaning cycle the drum rotates while spray jets wash the screen using pressurised water. The trapped waste is then flushed out of the filter to drain. Because this process happens automatically, the drum filter maintains efficient mechanical filtration at all times.

Flexible Flow Design

The BD 300 Combi MK3 includes a flexible outlet configuration designed to handle higher flow pond systems.

The filter includes:

3 x 110 mm inlet connections
2 x 110 mm outlets after the biological chamber
2 x additional outlets positioned before the bio chamber

Burtons recommend drawing no more than approximately 20,000 litres per hour through the biological chamber. If higher pond circulation is required, the additional outlets allow extra flow to bypass the bio chamber while still passing through the drum section. This design allows higher pond turnover without compromising biological filtration efficiency.

Optional Internal UV Clarifiers

The BD-300 Combi MK3 is designed to house up to two 20 watt submersible UV clarifiers inside the drum filter. Installing UV units internally provides two benefits:

Firstly, UV light eliminates free floating algae that causes green water. Secondly, UV light helps prevent biofilm forming on the drum screen. This helps keep the drum screen cleaner and reduces the number of cleaning cycles required.

Why the Burtons BD300 Combi MK3 Is One of the Most Popular Koi Pond Filters

The Burtons BD300 Combi MK3 is widely regarded as one of the best combi drum filters available for medium to large koi ponds.

Unlike many retailers who simply sell pond equipment, we design and build koi ponds ourselves. As professional pond builders and filtration installers, we have hands on experience installing and maintaining drum filters across many different pond systems.

From our experience, the Burtons BD 300 Combi is the number one combi drum filter we install for koi ponds in this size range. The reason is simple. It combines reliable drum filtration with a large moving bed bio chamber, creating a powerful all in one filtration system that is both easy to install and extremely effective.

The drum section removes solid waste before it can break down in the pond, while the biological chamber provides a stable environment for beneficial bacteria. The new MK3 version improves this even further with the upgraded 150 litre biological chamber, allowing the filter to handle higher fish loads and maintain stable water quality.

Because we build ponds and install filtration systems ourselves, we only recommend equipment that we trust and regularly install on our own projects. Combined with the 150 litres of free biological media included with every unit, the BD 300 Combi MK3 provides exceptional value and a proven filtration solution for koi pond owners.

Please note that stock levels can change quickly on Burtons drum filters, particularly during busy periods. If your chosen model is not immediately available from stock, a member of our team will contact you as soon as possible with an estimated delivery timeframe which could be as high as 2-4 weeks.

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Key Features

• Self cleaning drum and biological combi filtration system
• 60 micron stainless steel drum screen
• Integrated biological chamber supporting up to 150 litres of media
• Supplied with 150 litres of free biological media
• Maximum drum flow rate 35,000 litres per hour gravity fed
• Maximum drum flow rate 25,000 litres per hour pump fed
• Three 110 mm inlet connections
• Two outlets after the biological chamber
• Two additional outlets before the bio section for increased circulation
• Weatherproof control box with integrated socket panel
• Optional installation of two internal 20 watt Burtons Standard Submersible UV or Burtons Amalgam Submersible UV
• Low energy automatic cleaning cycle
• Designed and manufactured in the UK by Burtons Aquatics

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Technical Specifications

• Manufacturer Burtons Aquatics
• Model BD 300 Combi MK3
• SKU BA BD 300 COMBI MK3
• Maximum Flow Rate Pump Fed 25000 litres per hour
• Recommended Bio Chamber Flow approximately 20000 litres per hour
• Drum Screen 60 micron stainless steel
• Biological Chamber Capacity up to 150 litres media
• Inlets 3 x 110 mm
• Outlets 2 x 110 mm after bio chamber
• Additional Outlets 2 x 110 mm before bio chamber
• Dimensions 1470 mm x 680 mm x 720 mm
• Standby Power Consumption 1.3 watts
• Cleaning Cycle Power Consumption 150 watts
• Water Level 170 mm below top of unit
• UV Compatibility up to 2 x 20 watt internal UV clarifiers
• If adding Uvs to this unit you will need 1 stainless steel Uv fitting per UV

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Other Burtons Drum Filters in the Range

Burtons Aquatics manufacture a wide range of professional drum filters designed for koi ponds and large ornamental ponds. Each model offers the same reliable self cleaning mechanical filtration while supporting different pond sizes, flow rates and installation types.

If you are comparing drum filters for your pond, the following models are also available within the Burtons range:

Combi Drum Filters

Burtons BD 150 Combi Drum Filter
A compact drum filter with integrated biological filtration, designed for smaller koi ponds and installations where space is limited.

Burtons BD 300 Combi Drum Filter
A drum filter with integrated moving bed biological filtration, providing a compact all in one filtration solution for koi ponds.

Drum Filters

Burtons BD 300 Pond Drum Filter
A high performance self cleaning drum filter designed for medium sized koi ponds with flow rates up to 35,000 litres per hour.

Burtons BD 500 Pond Drum Filter
A larger capacity drum filter suitable for heavily stocked koi ponds requiring flow rates up to 55,000 litres per hour.

Burtons BD 700 Pond Drum Filter
A high capacity drum filter designed for large koi ponds and demanding filtration systems requiring high water turnover.

High Through Flow Drum Filters

Burtons TF 500 Drum Filter
A through flow drum filter designed for high flow koi pond systems with multiple inlet connections and efficient mechanical filtration.

Burtons TF 700 Drum Filter
A large capacity through flow drum filter suitable for larger koi ponds and professional pond filtration installations.

Burtons TF 1000 Drum Filter
The largest drum filter in the Burtons range, designed for very large koi ponds, lakes and commercial aquatic filtration systems.

Helpful Burtons links and compatible products

Use these links to compare the rest of the Burtons filtration range and plan the supporting equipment around this product.

• Burtons BD 300 Cube with UV
• Burtons BD 150 Combi Pond Drum Filter
• Burtons BD 300 Pond Drum Filter
• Burtons BD 500 Pond Drum Filter
• Burtons BD 700 Pond Drum Filter
• Burtons TF 500 Pond Drum Through-Flow Filter
• Burtons TF 700 Pond Drum Through-Flow Filter
• Burtons TF 1000 Pond Drum Through-Flow Filter
• Burtons Submersible UV Clarifiers
• Burtons Submersible Amalgam UV Clarifiers
• Burtons Bio Flo+ Media
• Burtons Bio Tube Media
• Burtons Drum Screen Cleaning Powder
• Browse Burtons drum filters
• Read our drum filter guide
• View Burtons UV clarifiers