Septic Tank Maintenance

Using EM in Septic Tank Systems 

Using EM-1 to control your septic tank system is a cost effective and safe method providing an environment friendly solution to the problems of odour and contamination from waste disposal.

How EM will help improve your septic tank system?

Your septic tank is the collection point for household sewage. Waste is collected and settles giving microbes a chance to break down the organic waste. The EM micro-organisms also ensure the liquid stays fluid and helps keep foul odour to a minimum. EM is a microbial inoculant, which contains live bacteria which need organic matter to continue to multiply. In a septic tank situation there is always enough organic matter for the micro-organisms to feed on.  By adding EM-1® your septic tank will stay working the way it should.

Common Septic Tank Problems

  • Anaerobic environment
  • Reduction in breakdown of organic matter
  • Increase in bad bacteria and pathogens
  • Foul odour
  • Increased sludge
  • Increase in rate at which tank needs to be cleaned out

Why these problems arise?

Modern cleaning products e.g. disinfectants, bleaches and detergents, are designed to kill the bugs i.e. bacteria.  Regular use of these chemicals can upset the biological balance of your septic tank by killing off the micro-organisms that do the work.  Extremes of temperature can have a similar effect.

Why you should use EM in your septic tank?

EM is a natural solution that works by increasing the microbial diversity of the system.  As more and more of us continue to use antibiotic soaps, and increase the use of bleach and other disinfectants, not to mention the intake increase of pharmaceuticals, the lifeblood aka ‘the biological balance’ of any septic tank system is put in jeopardy as the microbes start to die. The only way to revive it is to inoculate it with a strong, live culture of microbes like those found in EM.

Application Rates

Apply EM-1 , to recharge the system with beneficial microbes. This should be applied at a ratio of 1:10,000.

A 1 Ltr bottle of EM-1 is usually sufficient to treat a domestic septic tank for 12 months. If necessary repeat every 3 months.


EM treatment of water system for wastewater and polluted water like lakes and ponds works as follows:

The problem:

A surplus of organic waste mostly with a lower C/N ratio is going to the bottom of the water.

This surplus can come from human pollution or for example from algae growth.

When this organic matter start to decay ( broken down by micro-organisms) the micro-organisms are from an aerobe type. They use oxygen to digest the organic matter. The water becomes more depleted in oxygen and this results in even more decomposition of living organic matter ( fish) which will sink to the bottom of the water. In this oxygen poor water, the breakdown process will be taken over by the inorganic microbes ( fouling microbes). By breaking down the organic matter the microbes have to get rid of the free H ions which are released in the break down process. As they don’t like an acid environment they are searching for an acceptor, which is normally oxygen, but this isn’t available in an anaerobic environment. But in the decaying organic matter with a low C/N ratio, sulphur is available and sulphur can be used as a partner for the surplus of H+ leading to an increased level of H2S . Another gas which can occur is CH4 ( methane). The environment becomes a toxic environment and all the life in the water starts to die. The water will become very fouled and a rotting process will cause an awful smell.


1) Stop the infiltration of organic matter with low C/N ratio’s.

2) Try to aerate the water if possible.

3) Treat the lake with chemicals such as ferric which takes the sulphur away as FeS and gives oxygen in the NO3 form which will be used by the inorganic chemotrophic microbes.

4) Treat the water on a fermentative microbial way with photoautotrophic microbes.

Step one should be taken any how and step 2 will improve the recuperation speed but is not

always possible.

Step 4 is an interesting approach:

First we use fermenting microbes to ferment the in streaming organic matter. Just apply fermentative microbes in the surface of the water and let the ferment the organic matter/ The fermentation process doesn’t require oxygen and therefore the oxygen level in the water will stay on a reasonable good level and won’t decline during the decaying process. This will prevent that the oxygen level will decrease even more. Second step is to change the processes on the bottom of the water. To stop the rotting process we should provide more organic matter with a low C/N ratio will become available. By preventing and fermenting there will be less organic matter coming down and the organic matter which is going down has already been fermented. Due to this less and less desired food is coming available for the anaerobic putrefying microbes in the anaerobic water zone. For this reason their population will decline and the recuperation can start. But this is only the second step. To have a really good result we should try to get rid of the organic anaerobe sulphur rich decaying sludge from the bottom of the lake. To get the right microbes on the bottom of the water we house them in mud balls. The clay from which they are made are ideal houses for the microbes which not only helps us to bring them to the bottom and let them stay there. The mud balls can due to their weight easily reach the bottom of every lake or pond and stay there.. The balls contains a mix of microbes such as phototrophic microbes, lactic acid microbes and yeasts. As soon as they are at the bottom they find a feed rich putrefied environment in which phototrophic microbes can easily live. They use the sulphur and some wavelengths of infra read light to grow and are cooperating with the lactic acid microbes and yeast to create a less and less putrefying environment. In this cooperation they use more and more sulphur for making body proteins and the leftovers of the organic matter ( sludge ) starts to get eaten by other microbes for which the environment has become better now. The environment is changing and due to the fact that there is no oxygen demand on the in streaming water any more, the oxygen levels in the water will start to rise. The growing amount of fermentative microbes can be used by small living creatures in the food web as food. By this way the decaying has been changed in a constructive environment. The small life in the water will be used for bigger life and in the end by fish and humans. As life in the waters protein rich and protein is rich in sulphur de amount of sulphur at the lake will slowly go down and will disappear in the food web chain. So prevent polluted in stream of water. A simple water purification unit or even a reed bed can do wonders! Treat the water and the in streaming water with fermentative microbes and get microbes in mud balls to the bottom.

This is in a nut shell a description of how the system works.