Metro Bio Grease Digester Unit

Metro offers two types of bio dosing units: a drain dosing unit and urinal dosing unit (battery or mains). These units are small and compact and built to ISO Standards. Once we’ve completed the installation and commissioned the unit, it is fully customisable and will allow you to adjust the volume of product to be dispensed. These units have been designed by Metro Mechanical Services, drawing upon our many years experience within this industry.

The units are capable of dealing with the high volumes of waste encountered in commercial, industrial, food processing and fast food outlets.

Metro Bio Fluid

Blend of non-ionic surfactants, enzymes and highly concentrated, naturally occurring bacterial strains from the Bacillus that produces lipases, proteases and cellulose with an oxygen release system.


Metro Bio Grease Digester is a unique formulation containing natural non-pathogenic bacteria with enzymes, non-ionic surfactants and oxygen containing compounds.

This product was developed to breakdown all forms of grease and fats, proteins, cellulose and starches, which are normally difficult to eliminate and tend to clog and scale up the foul drainage systems.

Metro Bio Grease Digester works quickly and effectively within the drainage system with no harmful effects on the plumbing and drainage systems and does not create odours or noxious gases.

These bacterial strains are preserved using preservatives and become activated when exposed in water though a controlled dosing unit into the drain and shortly begin production of the enzymes required to biodegrade these Insoluble substrates.

The strains of bacteria are ravenous feeders of organic waste, as the digestive process begins, the grease, fats and organic scale are attacked and removed from the walls of the drains allowing them to maintain the operational flow.

The system offers key and clear advantages:

  • Highly effective with minimal odour
  • Frees and releases clogged drains without harm to drains and plumbing systems.
  • Completely biodegradable cleaning system.
  • Reduces all forms of fog and bod concentration from within the drainage system.
  • Neat and safe installation of the control system with easy interchangeable sealed containers.
  • Units can be calibrated to meet the demands of the individual site requirements
  • Units are fully mechanical operational with built in time clocks and dosing pumps.
  • No manual operation required by on site staff to dose the drains.
  • 50 preserved bacterial strains only activated when exposed to water to produce the required enzymes to maintain the drainage system
  • Easy installation to all types of drainage systems including treatment plants, pumping stations, grease traps and direct drain dosing.
  • Easy on-going maintenance requirements with a full field of plumbing and drainage engineers with 27 years experience backing up the product.


Sewage treatment plants and pumps

Metro Mechanical Services’ expertise in installing and commissioning sewage treatment plants is unrivalled.

Modern sewage treatment plants are rapidly replacing septic tanks as a much more environmentally friendly and long-term solution to waste management.

Extensive research and developments in this area has brought with it modern materials and techniques.  Sewage treatment plants actively harness natural processes, such as aerobic bacterial digestion, to help break down and neutralise sewage.

Today’s treatment plants are compact and extremely efficient, and come in sizes suited to anything from a large commercial development to a single household.


The following septic tanks and soakaway guidance notes may be helpful to you.  Sometimes it’s possible to solve some minor problems without expert help.  Although on occasion the problems are deep seated and need the assistance of trained drainage engineers.

Here are the typical questions asked by the drains contractor, they may help you to identify and sort out the problem.

Does water collect on the surface of the ground in the area of the septic tank soakaway?

This is a sign that your soakaway has failed, and is not allowing the untreated effluent to drain away effectively.

Do the drains ever become blocked and cause a ‘backup’?

Again, this can be a sign that your soakaway is not functioning correctly, is blocked by solids, and the untreated effluent is not able to drain away.

Are there offensive odours from the area of the septic tank or cesspool?

A septic tank does not treat sewage, but merely settles solids, and then allows the remaining untreated liquid to drain away. A cesspool simply contains the effluent and requires regular emptying. Both methods often result in nauseous smells.

Does the septic tank drain into a watercourse or ditch?

Some older installations may drain into a nearby watercourse or ditch, allowing untreated effluent to be discharged straight into the environment. This is illegal and the householder could be prosecuted.

Do you have to empty your septic tank more than once a year?

If you do, this is an indication that the tank is undersized for your property and is not functioning effectively. This in turn makes it expensive to operate and can lead to solids blocking the soakaway.

Do you rarely, if ever, empty your septic tank or cesspool?

If this is the case, then your tank may be damaged and/or leaking untreated effluent into the ground and therefore polluting the surrounding property and environment.

Have you extended or are planning to extend the property?

A septic tank or cesspool is designed to suit a specific number of people within a property. If this is increased then it is probable that the tank will require upgrading.

If you have a problem that needs professional assistance call Metro Mechanical Services on 0208 310 2000

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“Having used Metro Mechanical for a number of years now I am continually impressed with the excellent service that they provide…. Read more



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