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The Optimal Biological Conditions for Septic Systems

A wastewater system operates on the basis that a delicate ecosystem of beneficial bacteria is created, nurtured and maintained within its pipes and tanks. Like all living organisms, bacteria are only able to live in environments that meet certain requirements. 

The key to keeping a wastewater system operating efficiently is maintaining the optimal biological conditions within the system so that bacteria can maintain healthy populations and efficiently digest waste.

How waste is broken down

Mechanically, wastewater systems have evolved slightly, but their core function (which is biological) has remained unchanged since they were invented. All organic wastewater treatment systems break down waste using bacteria.

Waste digestion
  1. In the presence of a food source such as waste, bacteria produce enzymes which are catalysts that break up waste molecules.
  2. The enzymes break up large waste molecules into smaller molecules.
  3. Bacteria then consume the smaller waste molecules – digesting and turning the waste into water, carbon dioxide, methane and some residual waste.

Why biological conditions are important

Like any living organism, there are certain environments that are inhabitable and those that aren’t. In the case of humans, we need atmosphere that has at least 19.5% oxygen, temperature between 21°C and 60°C, and a source of nutrients with the most important being water. 

Similarly for bacteria, they have certain biological conditions within which they can survive, and more specific conditions within which they can thrive. 

If these conditions are out of balance – incorrect temperature, incorrect pH or insufficient nutrients – bacteria won’t be able to digest waste efficiently and in the worst cases they’ll die off. As it is with all living organisms, optimal biological conditions are imperative for healthy populations.

The optimal biological conditions for septic bacteria

These are the most important biological variables for wastewater bacteria and the optimal conditions within which they thrive.

Temperature Fluctuations


The optimal temperature for wastewater bacteria is between 25°C and 45°C. Too low and bacteria’s activity is inhibited, too high and they will die


The optimal pH level for wastewater bacteria is between 6 and 9. The right bacteria aren’t able to survive outside of this range.

Oxygen Content

Oxygen content

This varies depending on whether the wastewater system is a septic system or an Aerated Wastewater Treatment System. Septic systems feature anaerobic bacteria which don’t need much oxygen, whereas AWTS feature aerobic bacteria that require high levels of oxygen.

Nutrient Availability

Nutrient availability

While organic waste is what bacteria consume as food, they sometimes need specialised nutrients that aren’t readily available to maintain healthy populations. The same way while humans can survive on chips alone, we wouldn’t be healthy.

Factors that damage septic bacteria

Aside from the factors above being out of balance, there are external factors that impair bacteria’s ability to digest waste or kill them off completely.

Conventional Household Cleaners

Conventional household cleaners

The most prevalent and most damaging cause of low bacterial populations is the use of conventional chemical cleaners. The majority of household cleaners (even many that say they’re safe) contain harsh chemicals that are designed to kill bacteria. Using conventional cleaners when you have a septic, AWTS or greywater system will steadily diminish your bacteria levels.  Switching to 100% septic safe cleaners is the quickest way to prevent chemical damage.

Conventional Drain Cleaners

Conventional drain cleaners

The most common solution to a clogged drain is to pour a highly caustic chemical drain cleaner down the drain. If that drain leads to a wastewater system, it’s going to kill the beneficial bacteria needed for the system to function. Use a specialised septic safe drain cleaner to clear out drains leading to a septic system.



Another, often unavoidable, source of biological imbalance are medicines. Antiseptics, antibiotics and some cancer medications will pass through a patient’s body, enter the wastewater system and kill off bacteria.

Seasonal overloading

Rapid increases in the amount of waste or water entering a wastewater system can cause issues. With a sudden increase in waste entering your system, such as when you have visitors, the bacteria may be overloaded and find it difficult to cope. Similarly with too much water from heavy rain, laundry, dishwashing or showers, there isn’t enough time for sludge and scum to seperate. This means the bacteria don’t have long enough to digest the waste as a nutrient source and grow.

Temperature Fluctuations

Temperature fluctuations

Low temperatures inhibit the activity of most common beneficial bacteria which means they’re unable to digest waste as effectively. Likewise, very high temperatures will kill off beneficial bacteria. In most residential cases temperatures don’t fluctuate enough to cause serious issues.

Restoring and maintaining the optimal biological conditions for septic bacteria

The reality of modern day living and wastewater systems is that the biological balance within is constantly being upset. Household cleaners, medicines, drain cleaners and fluctuations in waste and water volumes are a part of everyday life.

The first and most effective way to manage and regulate these changes to your system’s biological conditions is to use a biological stimulant based wastewater additive. A biological stimulant based additive restores and maintains healthy bacterial populations by providing nutrients and stimulants which help bacteria overcome negative influences to their environment.

The second way to help maintain the optimal biological conditions is to reduce or completely eliminate the use of conventional chemical household cleaners. These conventional cleaners are the most frequent and harmful cause of low bacterial populations. Replacing them with 100% septic safe household cleaners will immediately improve your system’s health and lengthen it’s lifespan.

EcoCare Activator is a scientifically developed blend of natural ingredients, grease dispersants and biological stimulants that eliminates odours, breaks down waste and restores and maintains a healthy bacterial balance within your system.

The EcoShield household cleaning range is 100% septic safe, completely natural and is designed specifically for rural homes. Eliminate chemical cleaners and protect your wastewater system with the smarter way to clean.

What our customers are saying on Google

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