The Ontario Onsite Wastewater Association recently published a memo on their website about septic tank additives. The topic is one that does not have a consistent view across the industry. Some experts believe that their use is important to aid the functioning of the system, while others are not convinced they provide a benefit. The composition and marketing of these additives have evolved over time to meet changing demands and perception of septic system care in the industry.
The basic purpose of an additive is to aid the septic tank or bed in some way depending on the type. Additives fall into three types: inorganic compounds, organic solvents and biological additives.
- Inorganic compounds - These products are typically made from strong acids or alkalis, marketed to unclog drains. Their composition can kill healthy bacteria in the tank, allowing raw sewage to potentially pass into the bed. These compounds may also corrode concrete tanks, risking the tanks to leak its contents. These products are not recommended.
- Organic solvents - These products are considered a degreasers to break down fats, oils and greases. Good bacteria in the tank may be killed off, therefore allowing raw sewage to potentially pass into the bed. These products are not recommended.
- Biological additives - These type of additives, such as yeast, which are used to enhance the bacteria and microbes already present in the septic tank. Septic tanks have five types of waste: proteins, fibers, greases, pectins and starches. Biological enzymes are specific to each waste type - for example, Cellulase (enzyme), is specific to fibers and Protease is specific to protein-based wasted. The effectiveness of products depend on the health of the existing system and may not improve the efficiency of bacterial growth, reproduction, and function.
- Bacterial based additives: These provide a boost of live bacteria and aid in bacterial growth. In cases where healthy bacteria is lacking in the system, a bacterial additive may provide a boost the bacterial population in the tank. If the system already contains healthy bacteria, adding a commercial product may cause competition between the existing and added bacterial.
- Enzymes: These are non living and cannot reproduce and are intended to stimulate growth and reproduction of existing bacterial. It is understood that some enzymes may break down the scum layer and allow for fats, oils and greases to reach the septic bed.
Proceed with caution - products that claim to reduce or eliminate the need for tank pump out shall be used with caution. Many solids in the tank that require to be pumped out are ones that cannot be broken down using an additive. The accumulation of scum and sludge inside a septic tank cannot be completely prevented.
Expert opinions on the use of additives in a septic tank remains inconclusive. If you believe your system could benefit from using an additive, be sure to use a trusted supplier and a product that is environmentally friendly (look for the green eco-label) - anything that is put down your septic system will eventually make its way to the environment.
Want to ensure your septic system remains efficient? Follow a regular pumping schedule to remove any solid build up in the tank, clean your effluent filter and inspect the components of your system annually, and always consult a reputable expert when in doubt.
Ontario Onsite Wastewater Association: Septic Tank Additives - What you need to know!
Link: https://www.oowa.org/consumer-information/septic-tank-additives-need-know/
