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Klargester BioFicient 4 PRO Domestic Sewage Treatment Plant - 15 Person

£6,289.00
£7,546.80 (inc VAT)
£6,289.00 (exc VAT)

FREE UK 
DELIVERY

CUSTOMER OFFLOADING

BELOW
GROUND

SEWAGE
WATER

Discharge Type
Inlet Invert Depth
Quantity

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Product Description

This product is delivered directly from the supplier, lead times vary.

 

The Klargester BioFicient PRO wastewater treatment system is a complete domestic sewage treatment solution, designed for reliable, efficient performance, with flexible installation options to suit a wide range of sites. Supplied with a control panel, alarm and beacon as standard, the BioFicient PRO is a connectable system that enables early fault diagnosis and remote monitoring - delivering dependable wastewater treatment with greater peace of mind.

 

Product Highlights

  • Suitable for shallow dig applications
  • Invert options up to 2m (BioFicient 17 & 23 models and GRP tanks only)
  • Suitable for installation in traffic areas (structural advice required)
  • Low energy compressor
  • Lightweight yet robust design
  • A fully connectable solution - supplied with a control panel, alarm and beacon
  • Third party tested EN 12566-3
  • Efficient treatment technology & excellent ammonia reduction of 0.4mg/l
  • 3 year warranty
  • Affordable commissioning and service plans available for extra peace of mind
  • Free site visit to help select the model to meet your needs

 

Applications

  • Single/Multiple Homes
  • Barn Conversion
  • Small Office Development
  • Stable Yard Toilet
  • Farms
  • Offices
  • Light Industrial Premises

 

 

 

Model Reference BioFicient 1 BioFicient 3 BioFicient 4 BioFicient 5 BioFicient 6 BioFicient 17 BioFicient 23
Population Equivalent 6 10 15 20 30 35 50
Overall Diameter (mm) 1,540 1,425 1,920 1,920 1,920 1,920 1,920
Length (mm) 2,500 3,770 3,230 4,390 6,220 7,381 9,312
Depth (mm) 1885-2795 1830/2330/2830 2300/2800/3300 2300/2800/3300 2300/2800/3300 2275/2775/3275/3775 2275/2775/3275/3775
Inlet Invert (mm) 590-1500 (Gravity) 500/1000/1500 500/1000/1500 500/1000/1500 500/1000/1500 500/1000/1500/2000 500/1000/1500/2000
Outlet Invert (mm) - Gravity 690-1600 620/1200/1620 630/1130/1630 630/1130/1630 630/1130/1630 600/1100/1600/2100 600/1100/1600/2100
Outlet Invert (mm) - Pumped 1155-1555 320 320 Not Available Not Available Not Available Not Available
Material MDPE GRP GRP GRP GRP GRP GRP
Blower Ratings 50W 95W 115W 180W 225W 270W 270W
Product Weight (kg) 285 300 450 550 740 1200 1450
Cover Sizes 600 1,440/900 1440/900+600* 1440/900+600* 1440/900+600* 1000×600 + Ø600** 1000×600 + Ø600**

SKU: TANBIOFKLA038

Why Buy Your Tank from Direct Drainage?

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Need help choosing the right tank? Call our team on 01388 537050.

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CUSTOMER REVIEWS

Rated 4.8/5 by Direct Drainage Customers

Based on over 600 verified reviews

VERIFIED REVIEW

Very helpful from the start to the finish

Items were despatched quickly and arrived the next day. Would recommend.

Title

North Hayne Farm Cottages | 26 June 2026

VERIFIED REVIEW

Cheapest price I could find for the pump

Cheapest price I could find for the pump and delivery the next day what more could you want.

Title

Sam Jukes | 5 November 2025

VERIFIED REVIEW

Great service!

I ordered a septic tank it was delivered within a week and the delivery driver left it in the exact right place and time. Would definitely use this company again, thanks so much.

Title

Eve Harland | December 2025

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FAQs

From choosing the right treatment plant to installation, maintenance and UK regulations, we've answered some of the most common questions to help you find the right solution for your property.

What is the difference between a septic tank and a sewage treatment plant?

A septic tank separates solids from wastewater before allowing the liquid to drain into a suitable drainage field. A sewage treatment plant goes a step further, using biological processes to treat wastewater to a higher standard before discharge. Sewage treatment plants are often the preferred choice where improved treatment performance is required.

What size sewage treatment plant do I need?

The correct size depends on the number of people your property is designed to accommodate, the expected wastewater flow and the type of property. Sewage treatment plants are commonly rated by Population Equivalent (PE). It's important to select a system with sufficient capacity to handle your property's requirements. Our team can help you choose a suitable system.

Do sewage treatment plants need electricity?

Most sewage treatment plants require electricity to operate components such as air blowers, pumps or control systems. However, power consumption varies depending on the manufacturer and model. Some systems use low-energy technology to help minimise running costs. Always check the individual product specifications before purchasing.

How often does a sewage treatment plant need emptying?

Sewage treatment plants require periodic desludging to remove accumulated solids. This is commonly carried out at least once a year, although the frequency depends on the system, usage and manufacturer's recommendations. Regular servicing and maintenance are also essential to maintain performance and help prevent costly breakdowns.

Do you supply replacement parts for sewage treatment plants?

Yes! At Direct Drainage, we supply a wide range of sewage treatment plant spare parts, including air blowers, diaphragms, filters and other essential components. Whether you're carrying out routine maintenance or replacing a faulty part, our team can help you identify a suitable replacement for your system.

Do you stock all tanks and sewage treatment systems?

We do not stock tanks and treatment systems as standard. These are supplied directly from the manufacturer. The lead times of these systems will vary. If you need an accurate delivery date, please contact us on 01388 537050.

Are your prices inclusive of VAT?

It is important to note that all prices listed on our website exclude VAT. VAT will be calculated at checkout.