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Klargester BioAir 4 Economy Sewage Treatment System (up to 12 person)

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The latest Klargester BioAir 4 Economy 12-person unit applies aeration technology to elevate wastewater quality before discharge. The Klargester BioAir Economy offers flexible installation options to suit domestic dwellings with a low visual impact and is supplied as standard with an Isolator Switch (the Economy version is not supplied with a control panel) and has a standard 12 months standard manufacturer’s warranty.

This reliable, low-maintenance sewage treatment system offers efficient treatment of wastewater with little effort, making it the ideal choice for residential properties seeking easy waste management.

Klargester BioAir 4 Gravity Drawing

Klargester BioAir 4 IPS Drawing

Klargester BioAir Blower & Duct Vent Drawing

Klargester BioAir 4 Installation Guide

Klargester BioAir PIA Certificate

Klargester BioAir 2, 3 & 5 Extension Necks

BioAir 4 Features: 

  • Suitable for shallow dig Installations
  • Suitable for use in traffic areas (structural design advice required by others)
  • Low level visibility
  • No plastic media
  • Improved effluent quality – BOD5 97.5%
  • Third party tested to EN 12566-3
  • Easy to install and operate
  • Supplied with isolator switch (High Level Alarm optional on IPS unit)
  • Affordable service plans available
  • Robust and Lightweight
  • 3 years warranty* (terms apply)

BioAir Applications:

  • Single & Multiple Homes
  • Light Industrial Premises
  • Small Offices
  • Farms
  • Barn Conversions



BioAir 4

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Inlet pipe work*



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Our shipping costs cover most of the UK - however, parts of England, Scottish Highlands and Islands including areas north of the Glasgow / Edinburgh border, Isle of Wight, Channel Islands, Isle of Man, Anglesey, Western Isles, Shetland Islands, Orkney Islands, Isles of Scilly, Northern Ireland and the Republic of Ireland may cost more.
Please call before ordering if the delivery postcode is listed below. There may be additional shipping costs. AB, BT, CA, CT, DD, DG, EH, FK, G, GY, IM, IV, JE, KA, KW, KY, LD, LL, ML, PA, PH, PO 30-41 (Isle of Wight), SA, SY, TD, TN, TR, ZE Southern Ireland
Our lead times should only be used as a guide and are subject to change.


Unless a hi-ab delivery has been booked at additional cost, it is the customer's responsibility to offload with suitable equipment on the day of delivery and a failed delivery may result in additional charges.
We recommend installers and/or plant hire & materials to install such as excavators, aggregates etc are not booked until you are in receipt of the goods. Tanks Direct cannot be held responsible for costs incurred due to unforeseen delays, please see our terms for more details.
Give our friendly team a call on 01388 537 050 or email

If you are unsure or need help we are here to help! Give our friendly team a call on 01388 537 050 or email

Free Delivery is available to the whole of the UK Mainland (including Scotland) and is subject to suitable access for a large goods vehicle. 

This product is delivered to the kerb and it is the customers responsibility to provide suitable mechanical offloading facilities (eg. Loader or Excavator) to offload this tank safely. Please specify any access restrictions on your order.

If we can do anything to make your purchase more accommodating call our friendly team on 01388 537 050 or email prior to placing your order.

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