A septic system is a water tight tank through which domestic waste water is collected for primary treatment onsite, instead of being transported via mains sewage plumbing to a waste water treatment plant. The tanks are emptied periodically and have a system where treated effluent is disposed of via onsite drainage.
Septic systems can no handle excessive amounts oils or grease, food or chemicals. ‘Flushable’ wipes or liners should not go into the system, instead should be dispose of in general waste.
Products That Can Be Used With A Septic System
All detergents sold in Australian supermarkets are now either phosphorus free (P) or contain very little phosphorus (NP), any with the symbols P or NP all suitable for use with septic systems. If they comply with the biodegradability standard for detergents they are also suitable for grey water or biocycle systems.
All mainstream detergents eg. OMO, Dynamo, Biozet, can be used with a septic system without issue.
Stain removers, boosters and soakers eg. Vanish/Napisan, Sard, can be used with a septic system without issue.
Bleach can be used sparingly, as it breaks down into salt water and oxygen in the system, otherwise it can be disposed of on paving. It should not be used undiluted.
Products That Can Not Be Used With A Septic System
Disinfectants with the active ingredient Benzalkonium Chloride eg. Canesten, Dettol, generic disinfectants, should not be used as they do not readily break down, they are detrimental because they will kill the bacteria in the system. Same applies for anti-bacterial products and pesticides.
Caustic products such as oven and drain cleaners, and ammonia based cleaners should also not be used as the concentration is too strong for the system.
Another very important safety factor regarding septic tanks is that they should be completely covered with the covering made of a strong material. The covering should be checked periodically. There should also be signage around and on the tank as a warning to prevent people from walking on it. People have been known to fall through coverings that have degraded or have been damaged over time, and drown in the tank. The effluent inside acts like quick sand, and becoming submerged is fatal.