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GRAF One2Clean Xtra 5PE 3750l Sewage Treatment Plant | G50400

£2,670.00
£3,204.00 (inc VAT)
£2,670.00 (exc VAT)

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Product Description

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

 

The GRAF One2Clean Xtra Sewage Treatment Plant is an advanced wastewater treatment solution designed for homeowners, self-build projects, small developments, and commercial properties that require reliable, high-performance sewage treatment. Building on the proven success of the original One2Clean system, the Xtra model delivers enhanced control, simpler maintenance, exceptional treatment performance, and some of the lowest running costs available in the UK. Using innovative SBR (Sequential Batch Reactor) technology, the One2Clean Xtra achieves outstanding effluent quality while maintaining ultra-low power consumption. The system is particularly suited to properties in environmentally sensitive locations, with options available to support nutrient neutrality requirements and stricter discharge standards.

Designed with installers and homeowners in mind, the One2Clean Xtra features a flush-to-ground lid for discreet installation, an integrated sampling chamber, optional vehicle-loading covers, and a unique maintenance-friendly design with no moving parts or electrical components inside the tank. All servicing and operation are managed externally through an advanced control panel, reducing maintenance complexity and improving long-term reliability. The optional sludge removal pipe allows safer and cleaner desludging without disturbing internal components, while the intelligent control system provides enhanced monitoring and compatibility with additional accessories for greater convenience and peace of mind.

With quiet operation from as low as 36 decibels and energy consumption from just 0.63 kWh per day, the One2Clean Xtra offers an economical and environmentally responsible alternative to traditional sewage treatment systems. Available in capacities from 5PE to 70PE, it provides a scalable solution for domestic and commercial wastewater treatment applications.

 

Key Features & Benefits:

  • Advanced SBR sewage treatment technology
  • Outstanding effluent quality for compliance with strict discharge standards
  • Optional nutrient neutrality configuration for sensitive locations
  • Ultra-low energy consumption from 0.63 kWh/day
  • Quiet operation from as low as 36dB
  • Optional desludging pipe for safer maintenance
  • Advanced control panel with enhanced system monitoring
  • No moving parts or electrical components inside the tank
  • Flush-to-ground lid for a discreet appearance
  • Integrated sampling chamber included
  • Optional vehicle-loading cover available
  • Cost-effective gravel backfill installation
  • Optional raised outlet to reduce excavation requirements
  • Available from 5PE to 70PE capacities
  • Suitable for domestic, self-build, commercial, and development projects
  • Durable, high-quality construction engineered for long-term performance

 

Ideal Applications:

  • Off-mains properties
  • Rural homes and cottages
  • Self-build developments
  • Renovation projects
  • Small commercial premises
  • Holiday parks and lodges
  • Multi-property developments
  • Environmentally sensitive sites requiring high treatment standards

 

Biological Oxygen Demand (BOD) Suspended Solids (SS) Ammonia (NH₄-N) Phosphate (Ptot) Nitrate (Ntot)
7 mg/l (98.4%) 14 mg/l (96.6%) 0.5 mg/ (98.3%) 1.6 mg/l (80.2%) 7.9 mg/l (87.0%)

 

Population equivalent (PE) Max. daily flow [l/d] Max. organic load [kg BOD5/d] Total volume [l] Length [mm] Width [mm] Height [mm] Weight [kg] Product code
5 750 0.3 3750 2280 1755 1880 150 G50400
7 1050 0.42 4800 2280 1985 2110 185 G50403
9 1350 0.54 6500 2390 2190 2390 220 G50406
12 1800 0.72 8500 3500 2040 2515 380 G50430
15 2250 0.9 10000 3520 2240 2575 455 G50433
19 2850 1.14 13000 4000 2420 2755 510 G50436
24 3600 1.44 16000 4590 2500 3160 890 G50450
32 4800 1.92 22000 6230 2500 3160 1085 G50452
45 6750 2.70 32000 8555 2500 3160 1430 G50454
50 7500 3.00 38000 9925 2500 3160 1630 G50456
60 9000 3.60 44000 11440 2500 3160 1840 G50458
70 10500 4.20 48000 12140 2500 3160 1970 G50460

 

3750L Drawing
GRAF Brochure
GRAF Certificate

SKU: TANONE2GRA007

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Rated 4.8/5 by Direct Drainage Customers

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Very helpful from the start to the finish

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

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North Hayne Farm Cottages | 26 June 2026

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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.

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Sam Jukes | 5 November 2025

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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.

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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.